Mixed feelings about baby

My whole life I wanted to be a mom. I wanted a baby so badly. I did everything the "right way". I'm just so unhappy now. I don't know if it's hormones or what. I feel like I'm not even bonding with my baby at all. I feel so miserable with my s/o. I don't even want to be married anymore. My s/o knows I am unhappy and have been for awhile. I was thinking the marriage wasn't going to work and then I found out I was pregnant the next day. My cycles aren't regular. They can be up to 56 days apart. We hadn't done anything in awhile before finding out due to those feelings and haven't since I found out I was pregnant. I don't believe you're obligated to stay with your child's father because the child will see the unhappiness, but you should at least try. I just don't know what to do. I want to be happy about the baby, but I feel like everything else is making me too miserable to be able to.