Actor Mickey Rourke outside the Ed Sullivan Theater for the Late Show with David Letterman New York City, USA March 05, 2010. (HRC/WENN.com)

Mickey Rourke is determined to remain faithful to his girlfriend, insisting he couldn't live with himself if he cheated.

The Wrestler star has been dating Russian model Anastasia Makarenko since meeting her at a magazine photoshoot last year and claims it's his most serious relationship in years.

And Rourke has vowed not to ruin their romance by returning to his womanizing ways - because he's learning to be accountable for his actions.

He tells Britain's OK! magazine, "I haven't f**ked around on her. I haven't been that way in 23 years so this is new for me and it's not easy. Sure, I could do something on the side but I've got to live with myself. That's something new for me - being honest in a relationship.

"There is still that part of me where I didn't care about repercussions or being responsible but when it was really dark and there was no daylight, the only person I could blame for my downfall was myself."

But Rourke has no plans to make their union official - admitting he hasn't even considered proposing.

He adds, "I haven't asked her (to wed)! I haven't thought about it yet. I've only had two girlfriends in my life. There was stuff in the paper about me being engaged but it's just embarrassing for Anna because she is very low-key. People that you think are friends can be cruel, and I don't have the best reputation in the world, so it's very easy for people to say s**t."