Also consider a ketogenic diet. Currently I'm experimenting with it. So far I like it. Prepare for some extreme insomnia in the beginning. This should be getting better after a week. Should not be a problem in your case as you are already spending 22 hours in bed a day.
I had a very nasty depression. Extreme mood swings. From very low up to neutral and back. (I never had manic episodes) Up and down, up and down... It was maddening. And extreme rumination. I discoverd acetylcysteine by accident. I didn't know it could help with depression. I felt its effects within an hour. I immediately went on the internet and searched for "acetylcysteine and depression". That is how I found above article. The internet is full of articles about the efficacy of NAC in relation to psychiatry. I used it for about 6 months. 3 * 600 mg daily.