Hi,
Unfortunatelly you can’t just remove your name from the mortgage.
I am in similar situation.
My plan is to get injunction order for him and to sell the house. I will see solicitor soon, probably will know more details.
You may call Civil Legal Aid, answer the questions abd they will tell if yiu qualify for the legal aid. They also will give you solicitirs contacts in your area who works with legal aid scheme.
Local support groups may also organize for you legal advice.