If you are currently getting more money than you would after a divorce, I'd think seriously about not rocking the boat.
HOWEVER - I would check his credit report to make sure he's not running up any huge debts that you could be stuck with (you don't have any more joint cards, do you? I think since he's filed you are protected from new debt of his, but not positive. And check YOUR credit report to make sure there hasn't been any fraudulent activity in your name).
Also - are there 401ks he could be raiding, or kids' college funds? Try to gather as much financial info as you can.
Then, if it is to your financial advantage to stay where you are, do so - but rocking the boat about his stuff is risky to your current financial state.
Do you have a job? Should you be going to school to acquire new job skills? Anything you could get him to pay for right now (needed dental work, etc) DO IT. And if you don't have any funds of your own, think about trying to squirrel away a little extra cash for that rainy day. Or at least stock up on canned goods!
