For me it was mainly about stoppping sad or stressful thoughts as soon as they entered my head, not trying to reason with them or consider them, just saying 'no, I shouldn't go there'. I think stress is physiologically very bad for our compromised brains and trying to supress it and stay emotionally stable is important, though obviously difficult. Better to feel flat than to get into that whirlwind of stress and worry.

Also trying to find things I could do that still brought enjoyment. So at certain stages I couldn't read a book or watch tv without consequences but I could listen to an audiobook, so I got a load of audiobooks from itunes. For a while I couldn't do pubs, bars, clubs etc but I could go birdwatching with a friend in a quiet place. Think of things you might enjoy that are within your current capabilities and do them every now and then, to keep some pleasure in your life.

Also your post reminded me of a silly but somehow very comforting little thing I read recently: