Ex-NHS nurse Titmuss, who is now forging a career as an actress, admitted that her stint as a model left her feeling low and resorting to partying and drinking to boost her morale.
The former lover of TV presenter John Leslie told the Radio Times: "I clawed my way out of the hole I'd dug myself, but I know I wouldn't be sitting here were it not for all that. It did give me financial security, but it came at a great emotional cost.
"My self-esteem got so low, because I wasn't happy with what I was doing, that the only thing that would make me feel better was going out and partying and getting my picture taken."
After finding fame with Leslie, Titmuss went on to become a lads' mag regular and starred on porn channel Television X.
She commented: "I became the embodiment of something that I didn't have any respect for. I could never really deal with how brazen I was being on the outside when I was so lost and unhappy on the inside.
"I knew how third-rate I was."
Titmuss will star in an episode of Casualty later this month alongside Danny Dyer.
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