ED disputed

I cannot get my STBX to agree to a separation agreement. I told him I would be forced to file for ED and he has told me his lawyer said they will fight ED. Is this possible? I thought ED was strictly enforced in these situations.

They likely mean they will fight for more than half of the marital property. So long as you are married, living separate and apart and have assets and debts acquired during the marriage the claim can be filed and will proceed.