RACHEL Jackson is already waiting for me in a Kelvingrove bar this Glasgow afternoon. All Manga eyes, acrylic nails and toothpaste ad smile, she’s travelled up from Saltcoats where she lives, dressed in Spice Girl style, face glitter and a growing sense that things might just be about to happen for her.

You don’t recognise the face? Well, that is about to change. She’s not long finished shooting a new film about Glasgow’s rave culture (as was) made by Ken Loach’s production company. And then there’s her part in Karen Gillan’s directorial debut, The Party’s Just Beginning.

Gillan and Jackson, it turns out, have long been friends. They met at a wrap party in London, “two mad Scottish girls in the smoking area”, Jackson recalls. That was when they were both jobbing actors in London, long before Doctor Who came calling for Gillan.

And before all that hits the screens, there is the Edinburgh Fringe. This will be her third year.

This year's show, Rachel Jackson: Bunny Boiler is, as comedy shows go, probably not suitable for Radio 4. It is, says Jackson, about looking for “the one”, and the messy, freaky and sometimes downright disturbing avenues the heart can take you down. If nothing else, you will learn what “bagpiping” is. (No. Don’t Google it. It’s very NSFW.)

The term “bunny boiler” is, of course, drawn from the 1987 film Fatal Attraction in which married man Michael Douglas has a one-night stand with Glenn Close who turns out to be, well, not totally OK with Michael going back to his wife.

At one point, famously, Douglas walks in to find a pot boiling on the stove and … Well, you can presumably guess what is in it.

Jackson, so far as I know, has not boiled any leporidae. But she been called a bunny boiler. “A couple of times.”

It is a term of abuse, right? “Yeah. It’s not meant nicely. I’m trying to turn it on its head and make it fun. Because I’m not a psycho. I’m not going to get locked up. But I have done extreme things when I’ve been in love. Like we all have.

“I think everyone is a bunny boiler. Men, women, teenagers. When you love someone and it verges on the obsessive stage, love itself is a madness. The things that you think about when you are in love and the things that you do. You’re a more extreme version of the person you are normally.”

Extreme isn’t the word I’d use for Jackson. In our time together she comes across as a charming, potty-mouthed mixture of vulnerability, maybe a little bit of naivety and a huge dose of ambition.

Her Fringe show Rachel Jackson: Bunny Boiler is the third version of the story. She had a trial run two Fringes ago. “I was strictly just an actress then. I didn’t consider myself a stand-up at all. So it was more of a play. There was no interaction with the audience. There was no microphone. There was no banter. It was just – here is my monologue about my shit love life basically.”

Still, it was good enough to interest the BBC. Earlier this year she appeared in a series of short vlogs on BBC Three.

The new show is the most sustained take on the Bunny Boiler theme. It is a comic autobiography, drawing on Jackson’s own love life. “I’ve changed the names of some guys,” she says.

It’s not all hearts and flowers, it has to be said. “People come out saying, ‘The guys you were with are horrific,’” she admits.

“Not that I want people’s sympathy. I’m not crucifying them or myself. It’s all of us.”

Hmm, maybe. Frankly, it would appear the men in Jackson’s life in the past all seem to have a commonality of unpleasantness. There’s the guy who broke her hand on a date (not one of her best nights out, she admits), the “bagpiping” incident. (Same guy, actually. And what did I tell you about not looking it up?)

And then there was the man she calls the cult leader. He wasn’t responsible for any mass suicides, she quickly points out. He was just a bad guy, she says. “I call him a cult leader because he was a horrible person.” Jackson was with him for four years; he was domineering, she says, right down to trying to control what she wore.

Compared to that, when she later dated a Ukip voter, that could be seen as something of a step up? “Anything’s a step up from the cult leader,” she laughs. “Most people who come to see it go: ‘What? Does that mean you are a Ukip voter?’ And then I explain I was on a lot of cocaine at the time I was with that guy.”

Is she telling us that men are just fundamentally useless? “Oh God, no. I’m not saying all men are d***heads. Because at the end of the day I love men and that’s what’s got me into this mess.

“I think it’s only recently I’ve learnt respect. Bunny boilers in a way are so insecure. They’re so desperate for love that they’re searching for it from anyone, anything. I think I let that follow me a long time.”

How did she get past that? “My current boyfriend Michael. He’s an amazing boyfriend, the best I’ve ever had.” Jackson moved to Saltcoats to be with him and his children; they've been together for 18 months.

Before, she says: “He chased me. And I’ve never had that in my life. I was a bit thrown by it. It’s usually me who’s doing all the work. And so at first I wasn’t that into him because he already likes me. That weird mentality. Kind of game-playing I guess. Adult games.

“I think that’s when I eventually got past it; when I realised: ‘Jesus, someone likes you. You shouldn’t need to do all that.’

“But you have to be comfortable with yourself. And it took me a long time. A really long time. I’m 29 now.”

Still, on the upside, she says: “I got a show out of it."

Rachel Jackson grew up in Baberton (or “BABE-erton” as she’s taken to calling it) on the outskirts of Edinburgh in a working-class family who showered her in love and freedom. Her mother works in Mothercare, her dad in an office mailroom. Her brother was the “brainbox” and Jackson, well, she always wanted to be an actor and was never checked for it.

“I just remember being allowed to be confident, to have dreams. I hear a lot of people don’t. They are forced to have Plan Bs and forced to pick certain subjects at school, forced to train as a doctor and then they can go into acting. All these crazy conditions on their kid’s dreams. I’ve always been allowed to go for it.”

She had – still has – supreme confidence in herself. “Since I was little I always thought I was going to be a big deal.”

That confidence never wavered, even when she moved south and couldn’t get a sniff of an acting job. “I was living in London for seven years and even though I was pushing really hard, no casting directors wanted to meet me. A few adverts and things like that. Just getting tiny parts.

“But I never stopped believing. I don’t want to sound cringy when I say that, but I just know that these things do take time. Not everyone comes out of drama school and gets Game Of Thrones straight away.”

Actually, Jackson didn’t go to drama school until she was 25. “Most people go when they are 18 or 19. But I wasn’t interested when I was that age. I moved to London when I was 20. I was just doing dead-end jobs and sneaking off to auditions.”

But when theatre jobs kept getting away from her because she didn’t have drama school experience – “I was getting looked down on in auditions. Theatre can be really snobby” – she decided to go to drama school just to prove she could.

When she did: “I stood out like a sore thumb. There was only me and one other guy in the year who were working-class. The rest were really quite privileged.”

Jackson did a comedy audition speech at the audition. It got her a place. But then she spent three years playing what she calls “Keira Knightley” parts.

Perhaps the teachers knew there were only jobs for Keira Knightley types out there, Rachel? “Maybe it was that. But it just made all the other girls in my year hate me because they were Keira Knightley. They could see what they thought was a wee, chavvy Scottish girl with my gold hoops. And I’d see them f*** up comedy parts.”

Her own shift from acting to stand-up was unplanned. Before drama school she had appeared at a monologue slam event and won with what she thought was a serious piece. “But the audience were pissing themselves. My agent said: ‘You’re funny. You should try stand-up.’

She did, a couple of times, but it’s only been in the last few years that she has taken it seriously.

Here’s the question. Who’s needier – actors or comedians? “I think they’re both totally f***ing damaged in different ways," she says. "Actors are very insecure and desperate. But they’re generally warmer because with acting you’re with others so you have to be more empathetic. Whereas comedians are all for themselves. Actors are a bit warmer, but comedians are a bit smarter, quicker. That can be more dangerous in a way.”

I have to say I like this funny, feisty woman in front of me. She is unfailingly honest. “I would be lying if I said money wasn’t a motivator because I do want to have a nice life. All my life I’ve been poor so the idea that more and more money can come from it is exciting. I love holidays and travelling and going to nice restaurants. That would be a perfect day if money was not an issue.”

She points to the cup of tea in front of her. “Even there I had to ask how much for a tea. To get to a point where you don’t even think about it would be lovely. But how many people have that? Hardly any.”

Perhaps it’s no surprise then that she is fiercely ambitious. "Oh God, yeah. Like Lady Macbeth ambitious. But I say: ‘Act one, act two. Not act five.’"

So you're not ambitious to the point of madness? "I'm still together. If things don’t work out I would be Lady Macbeth, act five. At the moment it’s a good ambitious.”

Since she was little, Rachel Jackson has wanted to win an Oscar. Oh and she’d like to appear on Saturday Night Live. “Because Jim Carey, Will Ferrell, a lot of my favourite comedy people come from that. And when I tell people that they laugh. All my life they laugh in my face. ‘That’s nice Rachel, it’s not going to happen.’

“And I think: ‘How not? Because I’m Scottish?’ With the right amount of work you can get the green card and the visa and you’re there … I’m sick of people laughing at me for that. Now I have to do it. It’s fuel.

“Maybe,” she smiles, “that makes me a little bit crazy.”

The thing is, I say, it’s hard to square this steel-core self-belief with the girl who at 18 spent four years with the “cult leader”.

“I think that was more of a confidence thing. ‘Oh, this is maybe what I deserve.’ Which is really sad when you look back on it. But when you’re so young you don’t have much experience of how men or women are meant to treat you.

“When I came out of that awful relationship I felt free again. I was reborn. I was only 22 and I was acting like a 40-year-old divorcee.”

At what point did her self-confidence arrive then? “It’s something I’ve been battling with my whole life. My boyfriend and my friends say this about me. I’m very hard on myself. Although I appear very confident and outgoing and passionate, I am very self-critical and I am very down on myself. No matter what I achieve it’s not good enough."

She doesn’t see this as a negative though. “I see that the people who reach the top all have a bit of that in them. You need to have that. Never get complacent, never rest on your laurels.”

Rachel Jackson is somewhere between insecurity and self-belief, and between being able to afford a cup of tea and winning an Oscar. However far along that journey she gets, it will be fun watching her.

Rachel Jackson: Bunny Boiler opens on Wednesday, August 2 at the Pleasance Courtyard and runs until August 28 (except August 16)