Hey there, OP.
I doubt you're reading these anymore, but I will give you my opinion on your situation. I will bear in mind that I may be completely mistaken:
you, my dear, feel extremely bad about yourself. You have never learned to have healthy relationships with anyone, not even yourself.
the excitement and "high" that most people get from doing things they actually enjoy, from connecting in a genuine, caring, mutually supportive way with others, you get from indulging in attention seeking behaviors that you find satisfying because they give you positive strokes for your fragile self esteem.
the married men are there because they are low risk - they are already attached, so you don't have to reveal much of yourself and what you know you lack. you don't have to put in the work to maintain a good relationship. not only do you not know how to do that or what a good relationship is, trying to find out, up to this point, has just been too much for you. It's much safer and easier to just have sex with someone who is not a quality match. it makes you feel good, while at the same time saving you from having to look at your own inadequacies, to work on the things about you that you know are your own failings.
you owe your parents because it sounds to me like they are supporting you in several ways, and I suspect one of them is monetarily. you feel guilt because of this, and are building up resentment toward them because you do owe them, but you know you *should* be able to stand on your own two feet, but you *think* you are powerless to do so.
I say this only because I have been there, and I'm pretty sure you are in the same boat i was not too long ago.
You have children. Whether you see it this way or not, you chose to have them. Like it or not, you owe them everything. it is not something you can do over. Whether you feel suited to be a parent or not at this point, you are one. Like I said, you owe them everything.
you are doing nothing to address any of these problems. the married men are also a distraction from this fact - that you are doing nothing to change your life.
start doing something to change your life, and you will be far less troubled and far happier.
Live Cage Free!!!! or, at least be wild caught.
You can rebuild your self-esteem. Rebuild it into a way that others cannot destroy it anymore.