I am sure he does want some sort of friendship with you but that is HIS desire and it doesn't mean you have to adhere to it. It's unfortunate the WAS rarely thinks ahead of time that leaving a marriage pretty much shreds any option for a friendship. In most cases it simply doesn't work that way. Leaving a marriage is not okay but if it is the choice of the WAS then you are under no obligation to be his friend if you are not comfortable with that role.
IMO you (generally speaking) have to live your life based on what you feel is acceptable behaviors. I know your love your H but he does have a problem and since the problematic behavior is not a one time thing it won't just go away.
Have you thought about confronting your H and letting him know you are fully aware of what is going on (do not show him your proof!) and telling him that while you do care for him you cannot have somebody in your life (in any capacity) that participates in such dangerous behavior. If he opts to file for divorce then you have your proof to help with the spousal support. If he doesn't file at least you have set your boundary and for the time being things like bills will remain how they are.
If he chooses to stop paying the bills then you can file yourself (with your proof) and still have the spousal support (if I am understanding what your attny told you)
