I've had to deal with a lack of interest or pleasure for long periods. It was horrible. The worst for me was when I was on lithium....it was such a bad, horrible drug for me. I never thought I'd get better but I did, eventually. Then worse again, then better. I wish there was a permanent way to stay out of the pits of hell. I wish I had useful advise. You have my sympathies and I hope you find passion for living again soon. (((Hugs)))