Question: It is not something that many women are willing to admit, but I am most attracted to unavailable men. This has resulted in affairs that make me the other woman.
This dynamic is pretty satisfying for me, thrilling even - I know people would hate me for this but I get just the attention and excitement I want, and don't have to deal with the drudgery of a relationship. I know it is wrong on some levels, but I'm not sure I can convince myself to settle for something more conventional.
Answer: People make the choice to "settle" for healthier paths every day. Gambling, drinking, binge eating, heroin, cheating on taxes: It's not like having affairs is the only thing that humans have ever had to decide to do without, for the betterment of themselves and/or society - and yes, forgoing what they perceive as a thrill in the process.
Ultimately, you'll choose to stop if and when you decide that the costs are worse than the benefits.
It's a calculus that varies by person but ultimately comes down to this: What are your values? Not just ethics, though that's important - but also, what do you value in life?