Prolonged back pain

Hi im a 20 year old male and ive had extreme back pain since I was 15. I used to have a extreme sciatica which went away over the years and the pain has gone down significantly but now it is a constant 3-4/10 pain daily (given I don't do anything to make it hurt more that day). It hurts to sit down for long periods, stand too long, drive too long, carry things in front of me etc. I am very active and have been working out daily for nearly 3 years (I have also taken prolonged periods of time without working out to see if it made a difference but it did not), but only isolated movements which don't hurt my back. Any exercises/movements that put direct pressure on my lower back (squats, deadlifts, rows, sleeping on my side, etc.) will have me in severe pain for says but will return back to normal pain. I have had multiple mri's, xrays, and have been to countless doctors. Bone fusion, arthritis are both ruled out. I do have a slight herniated sic in L4 however they said it was normal and not out of the ordinary (and I have had a steroid injection for that specific reason). I have been and still going to multiple chiropractor with decompressions around 1-3 times a week every week for months as well as constantly in and out of physical therapy (which both help in the short term but yield no long term results). With all my X-rays and MRIs that I have received every time I was told there was nothing out of the ordinary. If anyone has had a similar situation I would like some advice on what I should do next, or any help regarding my situation.