Oh, your xh will get uglier for a while because the new gf is supporting his behavior, but eventually it will die down. He has absolutely no control over you or the children...he'll have to turn that control over on to the gf. Wonder how that will work out...lol!
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.
