I'm just wondering if an emotionally abusive woman wants out of a marriage and doesn't love or want anything to do with her kids can she get out of custody and child support in any state in the US? My wife has been throwing this in my face and has me worried.

No, a parent cannot legally voluntarily give up rights/responsibilities in any state that I am aware of, unless it is to clear the way for a stepparent adoption by their former partners new spouse or both parents are doing so for purposes of relinquishing the child for adoption. Even if the other parent agrees to it, the courts will not usually allow it as it is not in the child's best interests. Heck, in my state child support payments are set up to be taken directly from a bank account as a matter of course, due to so many failing to send checks on time. So she can threaten all she wants.

Also, I have to comment... You're still married to this woman? Are you two in therapy? That's a mean-spirited threat to make, and she sounds like she has some issues that should be dealt with by professionals.