It sounds like she is using you to make her and his life easier. I bet he knows about you and lets it happen because he can't be there right now. As soon as you've served your purpose you will get burned badly. The situation you're in will only result in pain, 3's a crowd and there isn't room for you. For her to bring the kids into it to guilt you is fucked up. You're right where she wants you and that will always be on the outside of her family. She has had 3 kids with dude and won't even kiss you, that should tell you where you stand. Don't get me wrong I'm sure you're really helping her out and I be she appreciates it but, that's all you are to her, is the the help.
Get your own family and it will be much more rewarding, if dude is a POS then that's not your problem.
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