Struggling with depression during pregnancy

So I’ll start from the beginning which is about 6 months ago. I broke up with my boyfriend of almost 3 years because of personal reasons having to do with both of us needing to grow up a little bit. We had a 9 month old at the time, now almost 15 months old. We do 50/50 custody, trading off every other week. We get along, have a good co parent relationship and can still talk to each other with respect. He was and always will be my friend and the father of my child and for that I love him. About a month and a half after breaking up, I started seeing someone semi casually. It got kind of serious and I am now 13 weeks pregnant with his baby. We had decided to keep the baby and that I would move in after the first trimester so he could help me through my pregnancy and everything post partum as well. However, the closer I got to moving in to his house, the more stress and anxiety I have started feeling. I told him my concerns and that I’ve decided to get my own apartment for the time being. To put it in perspective, I feel more stressed about moving into his house than I do about finding my own apartment and potentially being a single mother of 2. Now, I’m not sure if what I’m feeling is because I am overwhelmed with everything happening or if I really don’t want to be with this person. I have cried non stop for days because I feel sad and guilty if this relationship doesn’t go past co parenting. I just feel like everything has happened so fast and I need to focus on me and my babies before a relationship. I guess I’m just looking for some reassurance.