I wouldn't be so sure about that. You probably can't close it by phone if that is what you mean but you don't need both people whose names are on the account to be present at the bank to close it. (in my experience)

In 2000 abusive BF threatened my and my sisters'/mom's life so besides getting a restraining order I went to the credit union where the BF and I shared a checking account. I closed the account and opened one in my name only.

Start making photocopies of every financial document you can get your hands on while you are still living together.

I think your starting point should be to get advice from an attorney including an estimate of costs and what is an acceptable payment plan.