Man, how long is this gonna last? It feels like FOREVER
You have to quit looking at it like that. Think of a long term comedown as a prison sentence. It sucks but there is nothing you can do about it. You can 1) sit around and fret over the long time that you will be locked up OR 2) you can accept what has happened to you and do your best to better yourself and make it as painless as possible.
Use this experience and time to do some deep introspective soul searching.
Once I changed my attitude, I dug deep and worked out a lot of issues that I didn't even know I had. Before my comedown, I thought I was happy and had great mental health. Sitting down and trying to figure out the sources of my (comedown induced) newly manifested anxieties has done wonders for my expanded happiness and outlook on life post comedown.