Sometimes, your family lets you down and then it's time to choose a new support system.
You have people who care about you here, but you don't have anything preventing you from looking for others with similar issues in your community. New friends who're going through the same thing you are could help lift you up a little.
I found this support group near you:
It's more for bipolar & depression (which you mentioned you have), but I'd be very surprised if no one in the group has a loved with SZ, even if they're calling it bipolar or just don't have a better group to go to.
I haven't used it personally, but meetup.com is a good place to find others who share your interests.
I remember you have dogs - just taking them to the dog park or somewhere else dog friendly might help lift your mood.
It's easy to start feeling trapped when it's just you & your son. I go into the office 1/2 a day & work 1/2 a day at home so he's not alone so much. I'd don't know what I'd do without that time in the office, and sometimes I dread the weekends because I can't always get a break from him then. I don't need that break when he's doing well, but when he's not, it's a lifesaver. Otherwise, I start to feel trapped, angry, depressed, hopeless, you name it.
I also keep pushing the support group thing because I am definitely not the kind of person who does that kind of thing, but I'm so glad I found the one I go to from time to time. Even if I don't have much to say, I feel about 1000 lbs lighter when I leave a meeting just knowing I'm not alone.
This site is great, but I get really good, practical advice there from people who live near me and know the system we have here and how it works, right down to a doctor name if I need it.