ADVICE PLEASE

I'm 26 weeks and 2 days pregnant also have a 2 year old and feel like nothing I do is right . All I do is go to work and come home nothing else . I dont have any friends and have no car at moment . My SO on other hand works all day comes home for about 30 min than leaves with his friend for hours lately I've had enough and told him I feel like we aren't spending time together and I feel like I'm drowning here alone by myself with my 2 year old all day o understand my son isn't his but he does look up to him as a dad . All he says is he had a long day and I need to let him go out if he wants to because he feels his freedom is ending anyways when we have the baby . I don't think he's cheating on me but how can I explain to him in a better way that I'm depressed and desperately need him here more than just to sleep and eat together ? Am I being selfish idk what to do anymore this is killing me emotionally ...