Sarah or Nicky or someone else will probably be able to advise you better but:
- Is the account overdrawn? If not, then you could close it (might need a signature from ex) if there are no debts connected with it then it shouldn't effect him.
You could temporarily open a new basic bank account to use for the time being.
- If the account is overdrawn, as last resort could you transfer the balance to say another credit card? (wouldn't usually recommend this but if you're going to go B anyway....?)
Before thinking about petitioning for your bankruptcy, I would sort out the account first. If the account is overdrawn, you will both be liable for the repayments, it is probably fair to say, the bank will pursue your ex for the amount outstanding if you go bankrupt (this is if the account it overdrawn) If the account is in credit, it would make sense to split the money in an agreeable manner and close the account. You can open a new account, but it is possible a new account could be closed once you are bankrupt. At least if you do have your own account, your ex wont find out about your bankruptcy.
You would of course just need to transfer your payments into the account to wherever you choose to place your income, including any direct debits you have and benefits and maintenance.
As far as your accounts in your name, this has no connection with your ex, the bank will not request the money from him as long as they are in your name only.
After all is said and done though - you have done nothing wrong - remember this! Maintenance is paid in there and he did not make the effort to remove his name!