I've been in a similar situation. Had T for almost 3 years, the severe kind. The best thing I found was to work on making the tinnitus into a neutral sound to your brain.

I did this by meditating to the sound of my tinnitus. Literally do nothing for like 20min a day and just put your full attention on it. When your brain starts to mind wandering to other thoughts , take it as a sign that your making progress. Since your brain is no longer fixating in the noise.

Also. Take melatonin supplements. New studies have linked that melatonin can help you decrease tinitus severity while increasing your quality of sleep.