I had pre and post natal depression. I had a history of depression so knew I was at risk. I didn't like being pregnant and did not feel attached to my babyat all. Some days I think I thought I wouldn't care if something had of happened to her before she was born.
When she was 6 weeks old I developed PND and wanted to kill her, smother her with a pillow! Now that I think back on it, it's a horrible feeling, and scared me!
Anyway, turns out I have an auto immune thyroid disease (diagnosed march 08') that had been causing the depression for 8 years prior.
Good luck, you do get out of it. I love my DD now more then anything in the whole wide world and couldn't imagine my life without her