I just wanted to chime in and say that I have (had) very similar conditions to what you describe. There were times 6-7 years ago at its worst that I could not sit down, hobbled down the street, and nearly cried in bed because I was so uncomfortable. In fact, the only time I was pain-free was when I was on my bike.

I was going through a very stressful time in my life during that period. My work also had horrible office furniture, to the point that I threatened a workers' comp claim, and lo and behold, everyone in the office got ergo chairs and computer trays.

The thing that really helped me, however, was going to a chiropractor (who is also a PT) and beginning classical Pilates at a reputable and serious studio. The chiro work addressed immediate problems and my Pilates instructor provided me with modifications to accommodate my back issues while I gained strength. This was extremely important; I would never go to a "pilates"-type class at a regular gym. Only classical Pilates studios have properly and extensively trained staff in my experience.

The combination of directly addressing the stressors in my life and making huge changes accordingly (in my case), working with my chiro/PT, and dedicating myself to strengthening my entire core and body (not just "back muscles") has gotten back to pain-free, strong, and flexible. I'm in my mid-40s now and feel much younger than I did 7 or 8 years ago.

I no longer go to the chiro/PT, but i have continued with Pilates. If I stop doing Pilates for a time, I will experience twinges of pain after a while. That is my reminder that i need to refocus on my core strength. I am careful in the garden, and I always need to make sure that I sit properly at work and get up and move every 30 minutes (I use a timer).

I am now investigating the Alexander technique so that I can continue improving my posture. I will continue with Pilates; it has helped significantly in so many ways.

Best wishes to you. I would encourage you to seek out treatment (McKenzie is recommended by others with more knowledge than me) as opposed to doing things on your own. My PT is the one who recommended Pilates to me.