It certainly is as you describe ...malevolent almost like a curse. Would you believe I have continuous tinnitus as well.....both ends. You couldn't make it up. I am a bit younger than you 67 and was a very fit and active person doing 1 mile of swimming 2 or 3 times a week. I walked there and back to. I truly sympathise with your plight. I'm going to see an expert in this field in August. I am a bit concerned it might be autonomic neuropathy you see which would be if great concern. All happened in 2020 pandemic year. I wonder if that had anything to do with it. No tests then and there is no way of knowing either.