Im sorry your having to deal with this. I had a similar experience with my ex. He always came out on top. Always. I went to court countless times for child support and every last time he would pay 5-10 days before the court date so there was nothing the judge could do. He used to beat me and make me feel like I was worthless and I hate him for it. If that wasnt bad enough, he took my two girls one weekend and when I went to pick them up at our usual meeting place, he was passed out drunk in the passengers seat with his girlfriend driving. Needless to say, that was the summer of 1998. That was the last time he has seen the kids.
Remember, its not the kids fault, its these ex's who think they can do no wrong and they are KING.
You can do this. Your a strong women. Now go show him just how strong you really are.
I'm sending good vibes your way. Keep us posted.

Take care!!!