I discussed this with my Elder Law attorney. She said for that aspect of the situation she'd refer me to one of their Family Law attorneys. So I agree with Glad that finding a firm with multiple specialties would be a good thing.
You need a lawyer who understands Medicaid. There is a five year look back. You want to be sure you assets are split in a way Medicaid won't interfere if he needs it. You may also want to file as abused because divorces go thru quicker. And u have probably been abused somehow.