You are at a hard phaze right now with the detaching and the waitting. But now is the time to wait it out to see if your ex is really in fear of losing you or just a fear of losing.
Do not have sex with him unless it is something you truely want. (A lot of woman use sex as a means to try to keep someone in there life which does not really work in the way they intend it to) No matter how much he badgers you on this area of your relationship.I don't think it is productive to helping your sitch. No sense in letting him have his cake and eat it to. That can only cloud his vision to where he really stands and what he has done.
You are doing awesome.
I do have one question It seems ex comes to your house alot. Why? Is it on the pretense to see the kids? If so why always at your house. And at these times do you stay there or go off to do errands or things for yourself. Just wondering if this is enabling him to keep his sense of this is his house also and family atmosphere. Keeping him from sensing a lose of these things.