Just an opinion from a fellow tinnitus sufferer - I doubt that your T is a symptom of your anxiety. I think anxiety can increase T volume both from a strictly perception viewpoint (i.e., perceived volume increase but no actual increase), and a real volume increase that is physiologically based. Anything that stimulates the errant neurons causing the T will make it louder (or so I was told by a Mayo Clinic ENT). Anxiety is one such thing, but so is exercise, caffeine, and many medications including antidepressants. That doesn't mean all these things effect all people equally, however.
My point is, I think even if you get your feelings regarding your emotionally traumatic and clearly tragic event sorted out, I would not expect your T to completely disappear, but I would expect the T volume to decrease and that in itself will make it easier to habituate.
By the way, I have great empathy for anyone who has lost a child. I'm sorry to hear you have had to endure such a thing.
Wish you the best.