Telling your employer of a medical condition is a tough thing to do. In my case, I didn't have much choice. They all had noticed my stumbling around and the tremor. There was just no way to hide it. On top of that it took so long to get a diagnosis. The next day I went into my manager's office and told him what was going on. He was relieved that it wasn't drugs, alcohol or something like that causing my problems.
At that point he went on to tell the upper management. Within a few days they were bending over backwards to help me out. I worked for another 2 years before I just couldn't take the pace anymore. I don't know how much input your employer has on your getting SSDI but I got mine the very first time I applied with no problems. It's been 8 years since I retired and I still have someone from the company contact me every month to see how I'm doing and if they can do anything to help. I haven't been able to get them to give me more money as yet, but you just never know.

GregD