Having a baby with someone you hate

How do you do it… how do you escape the feeling of being terrified that your baby will look exactly like him? I am pregnant because I was raped. I actually thought the baby was my ex’s until I got an ultrasound and realized I was 3 weeks less than I should have been. That’s when I realized whose baby I am having. I try to be excited, but I’m uncomfortable. Uncomfortable knowing I’m not having a baby from the man I was and still am deeply in love with. I’m lost.