Can I add, having come across this thread for the first time, that you write and deal with the various suggestions with confidence?!
Confidence isn't a permanent state - how often do you hear sports commentators refer to a player or team losing confidence after a run of bad results.
Its always useful to remind ourselves of what we are good at, our successes. If you have a tendency towards perfectionism you will hear and dwell on the one critical comment and ignore the multitude of praise. Ultimately its like changing any habit - hard work.
My blog is about self confidence, my recent post
Dealing with Perfectionism gives more suggestions.
David