I'm sorry to hear that about your uncle, but it's great that you're there to help him. I think you should guide him in the path of realizing that although those sounds are bothersome, most of them are not that harmful. As a matter of fact, anxiety and fear of those sounds make tinnitus louder in some cases. The human ear isn't as fragile as we think. Damaged ears are more prone to damage, but there's a fine line between amount of damage a motorcycle revving by can cause vs. a plate hitting a sink. You should recommend him to wear earplugs or earmuffs when riding in the car, or going to the grocery store. He should also fix his diet and lifestyle if he hasn't already. (eating healthier, no alcohol, no smoking, no caffeine, exercising, getting sunlight, etc) Staying at home will only make him more depressed. Maybe start by taking a walk around the neighborhood and get accustomed to everyday noise, while having earmuffs on hand incase of motorcycles passing by. As for sound sensitivity, just try to be gentle at home with cutlery and drawers. And in public, wear earplugs to take the edge off of harsh and sudden sounds.
As for him wanting you to be there, I think he needs to find a hobby that can help him occupy his time such as reading, watching TV shows, drawing, meditating, etc. You need to let him know that although you do want to be there for him and hate seeing him depressed, you need to live your own life too. As for his depression, you should urge him to get at least one therapy session, just to see how it goes. If that doesn't work, buy some books for him to read! Buddhism books and self-help books definitely help with depression a bit.
I stayed at home for months because of my hearing loss and tinnitus. It only made me more depressed and I even developed severe OCD as a result. However, I learned to accept that every day noise isn't as damaging as I think it is, and even if it may spike my tinnitus, then so be it. We can't live life in hiding. To make up for it, I try to live as healthily as possible by eating a lot of foods that may help with tinnitus and protect my hearing. I also am aware of my surroundings. I move away from the source of loud noise if possible or run into the store before the employees put away the loud shopping carts. I don't stay in the kitchen when my mom is putting away dishes, and when I drive I try to drive slower and go carefully over bumps as to avoid excess noise exposure.
As for my depression due to hearing loss, I read some buddhism books that really put everything into perspective. My hearing loss came as a result of harmful habits that I've been doing. Those habits fueled my "suffering" and made me suffer more. In my case, those habits were listening to loud music, skipping meals, and sleeping late. Now that I realize what was fueling my suffering, I stopped those habits and as a result, my hearing and tinnitus somewhat improved. (not sure if psychologically or physically, but it helped!) There are lines in the book "The Heart of the Buddha's Teaching" by Thich Nhat Hanh that really struck me. It reads "Don't be imprisoned by your suffering" ... "Don't ignore your suffering, but don't forget to enjoy the wonders of life, for your sake and for the benefit of many beings" Although I have hearing loss and tinnitus at a mere age of 22, these lines made me realize that "you know what, I'm not going to let this make me throw the rest of my life down the drain. I'm not going to be scared of going here and there because of it." I'm not ignoring my "suffering" as I still try to eat, sleep, and avoid loud noises/places that may harm my ears when possible, but I don't skip out on living my life because of it. I still go to the grocery store if I need to, I'm just more careful with my surroundings. I still play with my nieces and nephews, but keep my distance so they aren't screaming near my ears. I still go to family parties, but take "noise breaks" every 20 minutes or so in a quiet room.
I'm not sure if this helps, but I hope so! I wish you and your uncle all the best. I hope he rediscovers his life and continues to move forward despite the tinnitus/sound sensitivity, so he doesn't have to rely on you so much. You're a great person for being there for your uncle. He's lucky to have such a great family member.
