It's not project-specific. It's not repulsive so much as slippery - I happily begin working, but constantly lose focus. I was diagnosed with depression over a year ago, but I'm on meds and it's pretty much gone, and I don't have trouble focusing on things that don't require much insight.
I've heard that anti-depressants can have a wide variety of side effects including things like this. Maybe look into the possible side-effects of the one you're taking?
P/S/A: There are single sentences which can create life-changing amounts of difference.