Failing relationship?

Chrissy
So I've asked a few of my friends and keep getting mixed answers. I'm trying to figure out if my relationship is failing or if I'm falling out of love or if this is just totally normal and will pass. I'm 20 and my bf is 22 and we have a 3 1/2 month old daughter. He has a car and a really good job that he's been at for 3 years so he's not super lazy or anything and I just got a part time job cuz we can't afford a babysitter or daycare yet. He works overnights and I work afternoons. Now here's what I'm worried about. Every morning when he comes home from work he either goes straight to bed or plays video games and either way I have to get up and take care of our daughter. I stay up with her all day and put her to bed at night when I get home. She usually goes to her grandma's while I'm at work so he can finish sleeping. Basically he barely sees her or spends any time with her or me. We have sex once a month maybe twice if im lucky and even when we do I cant climax anymore. This has all been going on since like a week after I got pregnant. That's about a year and we've been dating for a year and 9 months. When I ask for sex or even offer a bj, he's never in the mood or too tired. He seems depressed or pissed off all the time abd when I ask what's wrong and if everything's ok he says he's fine. I feel like he's put his wall back up. But the worst part of all this, I don't really miss him and I know I feel the way he looks. I'm depressed and lonely and can't stop thinking about how I miss my ex. I even dream of him. Does anyone have advice? Do I just need to give up? I know I really love him, I just don't feel like it's in the same way as before.