I suffer with back pain due to arthritis, curvature of the spine and a slipped disc so can sympathise as well.
Having a strategy not to snap is different for everybody. For me for many years was working in jobs I enjoyed, holidays to places I really wanted to explore and these days I have other ways to help me. When I had a major meltdown in 2005 I had already started keeping a journal and writing poetry so the next step was writing a book about my experiences. I had suffered with severe depression siince I was 19 although I have suffered with depression before then but I was officially diagnosed in 2005. For me writing has helped so much as there is a reason for being severely depressed and I had kept the anger that was related to it locked up insife so writing was also a release for that. I volunteer a couple of times a week, take my dog out a couple of times a week, that sort of thing. I don't have a (paid) job due to health reasons which includes arthritis in my hands so can go days of being in pain so volunteering helps in the respect that I get out and do something that I can do at my own pace.