Dear skoen... I have exactly the same problem as
you mention about sudden lack of self-confidence. I
have a run of bad/depressing days and then a welcome
day when everything goes well...like a bit of good
news for instance, It is a part of OCD that makes us
suddenly think we are no good or disliked. It does not
necessarily make me more obsessive, but a sudden doubt
(similar to an intrusive thought), that I am not doing as
well as I thought I was. But I know that in a day or
two I will be OK again. That is the thing that keeps
me going. All the best: RICHARD.