How difficult this must be for you. (((HUGS)))

If she left the relationship, she left the kids, makes no /minimal advances as far as contacting the kids then I would think it would be a no brainer to a judge.

I know this answer most likely already, but is she paying you child support. She should be if she is not. Any man would have to pay even if he didn't have a job or he'd be thrown in jail, so is she paying.

My sister in law, put in writing and her and my brother in law both signed an agreement that he didn't have to pay her child support and that he would never ask for custody or even partial custody. They both signed and had it noterized. That is as close to legal as they could get w/ out forking out to much money for a lawyer. He sees his son 3 or 4 times a year and agrees that the child will be better off w/ out knowing him well. He is most likely correct.

Is something like that something you and her could discuss. You keep custody and she doesn't have to give you support. You don't have to exclude them from her life just make sure they will not stay w/ her in a permanent living arrangement.