I've cut my foam earplugs so they have a rounder backside and don't cut into the sides of my ear.
I also have humongous ear mufflers, bought at the DIY store (store with building supplies). They are for people who work with heavy machinery and drills and saws and what not. Kati mentions the same: industrial ear protectors.
I actually went there and tried them all on until I found a brand that sat comfortable. We are sensitive people and small details matter. Of course they were the expensive ones. They've served me for 7 years now. Worth every penny.
Cheap ones will sit awful. Internet bought ones were terrible too. But order them anyway and see if you send them back if they don't sit right. Or just view the money spend on the bad ones as a means to find the right one. They are very much worth any price! I don't see you going to the store to try them out so order a few expensive ones online from a construction supply company. This is my strong advice. Ear mufflers will save your sanity.
I wear them each day for a bit. And let my body relax. Listen to my heart beating, the blood rushing by like it's the wind in tree tops. In 20 minutes my ears will get squashed or start to get sweaty. But that's 20 minutes of bliss and reminding that upbeat anxiety from noise is not the natural state of my body.
I'm sorry, there is no way you can talk your body into relaxing when there are these noises. You have to shut them out. Especially deep rumbling ones (diesel engines, generators, refridgerator, computer fans, heavy traffic)
I've gotten better healthwise and am more resilient towards noise now. I would not have believed it possible. But it started all with good ear mufflers. (and I still need them daily).

I have started each paragraph of this post with "I". I must be important

hope you get something from this. Noise is terrible. It keeps reinforcing the stress reaction your body is looped in at the moment. Go buy mufflers.