That's how you know when you've made the right decision - it feels good, even if the path ahead is difficult.
Your son deserves stability and your presence and your H must do his part to make sure he gets it. Definitely sounds like you know that and will make it happen - almost (but not really) feel sorry for your H!
If you plan to hang around on the board but move to a different forum, let us know so we can keep in touch.