Are you kids "both" of yours or just yours from a previous marriage/relationship?
Are you on a Quixotic quest? Dunno.
I think you made the right choice to set boundaries. It would be nice if you could kick her cheating a$$ out of the house sooner than later.
Sometimes healthy boundaries are the best form of getting a life. They show the cheater that you are someone to be reckoned with. Strength is attractive.
Don't pretend to get a life. Get one. Really. Try some things you might enjoy. Right now, however, the ONLY thing that seems to matter is getting her back. I might suggest a little healthy anger and outrage may put some clarity in your game.
She's got to feel that by leaving, she's going to lose you. You can't be her plan B.