@LisaS - you've described hour household to a T, other than I don't have any other children who could have moved out.
It got to the point that my husband pretty much moved out to a camper we have at some property we own in the country. He was out there every day anyway, so it wasn't a huge move. It's helped out a lot.
Now, we're thinking everyone would be happier if we put a doublewide or something out there as soon as we can afford it and we just maintain two households going forward. We're lucky to be in a position where we can do that.
It's funny. I believe my husband has bipolar - he's only been diagnosed with adult ADHD, which also fits.
Our son has been diagnosed with SZ, but I'm thinking SZA.
But, unless my son is having a full-blown psychotic break, he's much easier to be around than his father. My husband is exactly like yours - everything's a crisis, and he panics, then demands solutions right away, and before you can find the answer to one question, he's asking another one or asking for help with something else.
I'm lucky that I handle stress well - I deal with the situation as it happens, then forget about it after it's done.
I've done it so much I think I have nerves of steal when something really, really bad happens - as long as it doesn't involve my son. I totally freak out then. Or, I think I do. I probably handle it better than a lot of people do.