Hi Dizzy just read your thread and wanted to say I could have written your post after my DD was born in April. The anxiety/boredom/lack of sleep was totally overwhelming and I felt total panic when left alone with the baby, especially when she was crying, which was a lot of the time, I just didn't know what to do. I really wanted someone (anyone!) to rescue me.
I woke up every morning with a sense of dread and really thought that I should never have had a child as I was essentially a selfish cow who just wanted her old life back. I also completely lost my sense of humour, and HATED my DP (I found him utterly intolerable and am ashamed to admit I punched him in his sleep once...how dare he sleep!!!)
Also I hated going to mother and baby groups as I felt such a failure and couldn't seem to coo/cuddle/cope as much as everyone else. I couldn't even put the baby in a sling without almost dropping her...
As everyone has said it did get a bit easier after 12 weeks when the colic subsided, but I still felt rubbish and teary. At 4 months it got easier still but my mood didn't lift. But at 5 months I was diagnosed with PND and now, after a month and a half of taking anti-depressants I feel like a completely different person (well a bit like my old self+actually being a mum IYSWIM) and I'm starting to love this new way of being, and I absolutely love my DD, and even my poor DP - much to his and my relief!
IME the first 4-6 months were AWFUL, and I really don't know if I could ever do it again...although I'd love a sibling for DD, and of course having been through it once maybe it wouldn't seem so alien next time round .
So I hope things get better for you, as they have for me. I can actually relax now and even think and talk about other things... even on four hours sleep a night .
Good luck, your doing fab, and take care of yourself as well as the wee one.