I would lie to share my experience .I am sure it will give you some help/options.My ex tried doing the same thing (cut the phone,refused fill the groceries) .I immediately called my CAS worker(he called CAS twice on me .Tha same situation as you that I am unfit).So she came and filled the groceries and telephoned him.She explained him that if he fails to provide the necessities for me and my kids then CAS will take care of it which he will pay anyway with interest after the court order.He got scared and started the bill payments,grocery etc etc .
Also if it is a joint bank account only one party can close it.When I migrated to CANADA he told me "I GAVE THE CRA YOUR NAME SO THAT YOU CAN RECEIVE THE CTB CHECKS".And i was highly obliged

Then he opened a joint account and kept both the debit cards with him

.So when we separated and he refused to pay me even10 dollars in cash then I called CRA,requested the paper checks and closed the joint account myself.It took me full 3 years to understand that Women have rights here unlike INdia