Nui Chutawadee, who worked with Khanokporn Satjawat, said the pharmaceutical firm manager was loved by everyone.
Ms Satjawat was found dead within the ladies' toilets of the Clyde Auditorium on Monday.
G4S security guard Clive Carter has been accused of murdering the 42-year-old by beating her with an unknown weapon.
Ms Chutawadee spoke of her shock and sadness on learning of her friend's death. She said: "I heard from another friend about her death and it made me so sad and I panicked.
"I just saw her post on Facebook about this meeting in Scotland a couple of days ago before the bad news and I can't believe she's dead now.
"Khanokporn was a working woman who was very good at what she did in her job. She was always cheery and positive thinking and I could tell that everyone loved her, both colleagues and customers."
Ms Satjawat was attending as a delegate at an HIV treatment conference in the auditorium, also known as the Armadillo, when she was killed.
Paramedics were called but she was pronounced dead at the scene.
Just hours before her death, she had posted an image from the conference on her Facebook page.
Ms Chutawadee said both her friend's parents were dead, but she had an older sister she was close to.
It is understood that one of her friends, Jah Oh Pattaraporn, has flown to Scotland to organise the return of her body to Thailand.
Carter, 34, of Motherwell, North Lanarkshire, appeared in private on petition at Glasgow Sheriff Court before Sheriff Danny Scullion on Wednesday.
He is expected in court again next week for a further hearing.
G4S refused to comment.