I would assume an IC job with a single employer is easier to manage than founder or side projects or multiple consulting clients. Probably something where physical presence is required might actually be better (given that the rest of your life sounds unfulfilling). Not sure how limiting the chronic pain is for this, but finding something where you are provided housing/office/etc. at some location to do whatever work might be a good thing for a while (i.e. the tech equivalent of a remote oilfield job). These exist, but not sure how best to search for them. Might be a chance to transition from backend web dev to embedded, too.
(I was depressed/broke after a big startup failed and the dotcom collapse and crazy ex-gf in the bay area back in 2002; I went to Iraq/Afghanistan/etc for ~a decade to do tech stuff to get away from it.)
Good luck! (Also there's presumably some YC resource? idk, haven't really kept up on YC internal stuff for a while.)