Some of the very best advice on the whole dang internet is at Dr. Lastname's blog.
Here's another stupendous post:
"Depressed people prefer to listen to their rotten emotions telling them a
hundred reasons why they’ve failed, no matter how many victories
they’ve achieved, and people with bad habits can find a hundred reasons
for thinking they had no choice, despite the many avoidable fuck-ups
they’ve fucked up."
Ever been around a downer? Have I?
WHY YES, YES I HAVE.
It's a...well....it's rather..A DOWNER. If you let it.
So screw 'em.