Sorry you are having a bad time, not sure how to help you apart from saying I think I know how you feel.
Having a baby must be a very stressful time, I've not got children yet so I don't know how to help in that area. Is it possible you could have post natal depression? or maybe your partner is just a selfish twunt that is making a lot of things worse for you.
My sister didn't seem as affected as me, but interestingly we both live away from home, me around 150 miles away, and she lives in Australia. Neither of us are bothered for living close by and where I have always found it easy to form relationships, I don't feel that I ever truly 'let go'. My sister hasn't ever had a long term relationship yet, and I wonder if she is affected by it too.
Time on your hands is never good..! If I have too much time I get all miserable and inevitably end up looking at my past to try to establish why I'm so unhappy with things. Keeping busy keeps me sane and stops me thinking too much.
I also get upset very easily, but I'm a very confident and independant person. I wasn't always like this though, I've 'hardened' to life, which I can't decide if that's good or bad.
Anyhow, not sure if this is helping or not. But have you thought about a visit to the doctors, or even filling up the day more to try and stop the thoughts?
What is the connection between your partner being selfish and your parents lack of affection? Do you resent him because you think he will treat your child the same as you were treated perhaps?
G x