I'm sorry you're going through this, but I agree with the others...unless they feel he is in immediate danger to himself (suicidal or if he lets them take his blood pressure and it's extremely high) or danger to others, an ambulance will usually not take them against their wishes.
I'm sending you many, many hugs and prayers, as I can only imagine how hard this is. I also agree...is there somewhere you can go to just get away a little bit? I know you're concerned about him, but unless he's willing to do something to help himself, he's going to do what he wants, whether you're there or not.
As you can see, others have been through this, so maybe just hang around with us for a while. I know it's gotten me through some really rough times.
Hugs and prayers,
Amy