Is it tendonitis or Tendinosis? I had tendinosis in my elbow and bicept tendon for about two years, and it was just wrecked. I tried everything: massage, flossing, jointforce, rollers, deep massage, graston, cortisone, and ART. I was desperate and my only two other options were surgery and PRP. Two shots later I have almost no pain and are actively rehabbing it using theraband bar. I have been out of the gym since July (couldn't even lift a plate to put on the leg press) and i start back in the gym in three weeks doing very light work.
It's totally sucks but I ignored it and said fuck it because for the first time in a long time I looked really fucking good: total recomp over a year, before the injury. Lost about 5 inches off my waist and gained about 20lbs of muscle over that year and a half.
Now I am about 1/8 what I was then. But I will be back but slowly and listen to my body. No more super heavy grinding reps, if I don't feel like it that day...I will stay home. And if I tweak anything...no matter how minor I will lay off that area until it feels better.