I’ve kinda come around on cheating in the last few months.
Most people have horrible relationships. People get into them before they’re ready, and they’re too egoistic to be able to have real discussions about faults and work on their crappy relationships and crappy personalities.
An affair is an opportunity to capture a moment of happiness amongst all the dreck. If you really have a great relationship, then cheating on that is just the height of stupidity, but if your relationship is like most I’ve seen, then I’d say that if you can keep it discreet, then have fun.
My stance now on things like this is, if you’re going to do it, at least be an adult about it. His family is bigger and more important than your affair. So don’t go messing with it. At the same time, realize that you will never be able to have a life with him, and that every second you spend with him is a second you’re not out there finding your own relationship and your own family. Are you really willing to wait until his daughter is grown before he might leave his wife?
You should be honest with yourself and work to understand what it is that’s drawing you to a guy who is already taken. If you can learn something about yourself, then it’s worth it even if it goes nowhere.