Hi fren, sorry it's taken an age, work distractions.

Sounds tough times, I hope things improve all round for you.

I'm not very helpful with most things, but a few of these worked for Dad's tinnitus (though it doesn't sound as overwhelming as yours)

https://www.youtube.com/results?search_query=tinnitus+relief

There's a few to choose from, including a loud hissing which matches the tinnitus sound and neutralises it (supposedly). Dad could only hear the tinkling noises in the background, the 'white noise' was invisible to him (you might need to ask an observer for help to see if it's even playing...).

I have a feeling that they may not provide complete relief as yours sounds like quite a strong case, but may be worth a try. There's all sorts of new research being done on frequencies too, might be worth a look.