Unfortunately Wahine, your story is somewhat familiar. My xah did similar when I got a lawyer. I don't want to go into the gory details, but it is horrible what he has done to the children and I. I was truly unprepared for the living off of found change in the couch lifestyle we had to adopt when he cut off the child support and everything. He has dragged out our divorce for 18 months and it has been exhausting.
Be prepared for more of same and worse. Do you really still live under the same roof? I would call your local dv shelter or the national dv hotline for help. This is financial abuse. You say he hasn't been violent, but close to it. My xah got pretty crazy and dangerous when I decided the relationship was over and started to free myself. He still won't let me go, truly. He thinks he can control his family by destroying our finances. He doesn't seem to care what he is doing to his relationship to the children in the process.
Keep posting and seeking legal advice. But better to get what free help you can. Lawyers are costly and they don't always really care about whether they are helping you or just adding to their incomes. Inform yourself and take good care.
((((Hugs))))