The radio host, who has been a Big Breakfast star, revealed his personal problems at the weekend.
And yesterday he said he was worried he would die following a collapse after snorting the drug mephedrone - sometimes known as meow meow.
The incident, he said, was a wake-up call to the married star to sort his life out.
Ross, 57, brother of ITV chat host Jonathan, said he consumed a hefty quantity of the drug before collapsing in a hotel car park.
"I suddenly had this amazing clarity. I knew that I had to make a break with him and the drugs to try to keep my marriage alive," he said.
Ross claims he has not touched the drug for three weeks but the former teacher he had been seeing has tried to contact him at work.
The broadcaster's wife of 10 years, Jackie, discovered his secret by tracing his iPhone and heading to the flat where he had been using the drug. He avoided her and then fled to the car park where he collapsed.
In an interview father-of-four Ross described himself as an addict and said: "The person I have been over the last 14 months isn't someone I recognise. I have done things I didn't even think it was possible for a human being to do."