I had a similar experience with drinking alcohol not that long after I detoxed in the hospital. I'll admit that I did have cravings, but I "suddenly" thought that I could handle it again, but more in moderation.

I don't do much at all when I'm depressed. Of course my therapist and psychiatrist tell me "Push yourself and then you'll find it was easier than you thought" or "Push yourself a little and that will make you feel a little better". But it doesn't.