@MJM have you thought of trying vapes to help with stopping smoking? My oldest son (now late 30s) has been a smoker for most of his adult life. He managed to stop completely in about 3 months using one of these. DIL now also trying, trouble is I think she is enjoying the vape too much, it's become a sort of substitute - but at least it's healthier.
Glad to hear things are going so well for you - you sound like someone whose life is coming together.
I have had back problems which I think are due to bac. My theory is it relaxes your core muscles, so that any pre-existing problem (in my case a scoliosis) gets worse. I'm now doing yoga & pilates to try to limit the progression (I've said this elsewhere, probably repeating myself - sorry!)