I agree with the great advice from ((TheByzantine)) - just keep going and don't be judgemental of yourself. I find when a person's depresed, very often their creative side suffers - so if you're an artist, musician, writer etc - you'll likely feel flat and uninspired. For example I suffer from low grade circumstantial depression and I love writing and art - when I'm having a bad day I just can't come up with the words to express myself. Depression dampens creativity.

I agree - set small goals and it's okay if you fail or not completely awesome. I wonder if you've tried exercising, because this is a wonderful way to boost everything. I hope you will find some inspiration and get that 'zing' back.