Feeling down

This pregnancy has been really hard on me emotionally and I still have 15 weeks to go. My first pregnancy was so different. Now I rarely go a day without crying. I've never struggled with anxiety but I have struggled with it so bad since I got pregnant.

I mostly associate it with the lack of support I have. I'm starting to resent my SO. He is constantly making plans to go out drinking while I stay home with our 2 year old. If I make plans to go out with friends, he asks me to drop him and our son off at a friend's place, where he will spend more time drinking than hanging out with our kid and not think twice about it because I'm his built in DD. Because of this I feel like it isn't fair to my son if I go anywhere without him.

My SO has no interest in this pregnancy. He put his hand on my belly once and only because I asked him. I sent him some double strollers to look at a month ago and he still hasn't despite me asking multiple times. I've asked about baby names and he says no to nearly every single one of my ideas and has no ideas of his own. I'm never alone; I literally have a human growing inside me while my son is attached to my hip but I feel SO ALONE. I've told him that. I've told him I miss spending time with him and I hate that he has to be away from me to feel like he's having a good time. His way of fixing that was to ask my permission before making plans with his friends, which doesn't help because now I just feel like I'm either the bad guy who says no or I'm giving him permission to do something that will upset me while he has no guilt. I miss him all the time. I planned us a fun date night last weekend and left my son with my mom over night. We had a great time but he seems to feel like he gave me what I wanted and now he doesn't have to worry about my feelings for a while. When we talk about it he turns around and makes it about him: I'm different this pregnancy, he struggles with anxiety and depression, he has unresolved emotional issues associated with the birth of our first (long story but we were expecting a girl and he came out a boy. Everyone thought it was hilarious. It wasn't. It was very hard on us). I don't think it's fair that his personal issues are an excuse not to be there for me. We should be in this together.

I guess I just need to get it out. I know I'm more emotional than normal. I also know it won't be any easier once baby is here. How do I deal with the resentment I'm feeling? How do I stop feeling so lonely?