We've ALL heard the terms home-wreckers and man-stealers before and we know the stigma attached. However, I never hear people talking about the man who was involved in the situation. Men (or women) HAVE to be willing to leave their relationship in order to have an affair because a person who is DEDICATED to their significant other isn't going to end up running away with someone else. In my last relationship, there were many times where I was without him and other men would hit on me and try to convince me to go home with them. I was dedicated to my relationship and would repeatedly refuse, no matter how hard they tried. However, someone who isn't happy in their relationship in that same situation might just go home with someone else because their partner isn't there.
Of course, relationships are very complicated and sometimes, couples are willing to make it work even after one of them has cheated or had an affair. So, it doesn't always end in the home being wrecked, if you will.
However, it is IMPOSSIBLE to steal a man for multiple reasons. The aforementioned is the most important, but also the idea of 'owning' the person you're dating is quite f*cked up to me. Someone else in a relationship isn't your property to steal and someone who is single doesn't suddenly become your property when you start dating. I think it's toxic to think of your significant other as 'yours.' Sure, they're YOUR significant other, but they're not YOURS. They are their own individual person!
At the end of the day, some people just aren't good at being in relationships. Some people can't handle the commitment aspect of a monogamous relationship, and they are likely to cheat. However, you can't 'steal' someone who wasn't willing to leave in the first place.