How can we make it work??

I am 30 weeks pregnant and im not married but the father of the baby and I have been together for 1-1/2 years. but the past few months its like everything has been changing for us. He’s a sr in high school and im in my 1st yr of college. we live together and we’ve been having a lot of arguements because he dont like to clean house or do anything but sit around. And if he does try to help out he does it totally wrong and it ususally ends up with one of us leaving and we dont speak to each other for hours. We love each other but the only time we are even in the same room is while we are sleeping but lately he wants to sleep on the couch and he blames it on my belly getting bigger and needing more room. He’s always at school, with his friends, or at his family’s house and Im always either at school or work. I really try to make everything work for us and so the baby can be in a happy family but I have a feeling that if something doesnt change he’s gonna start a relationship with someone new at school behind my back because he has in the past. I really dont want to lose him but I need help around the house and if im the only one being responsible at home its hard. how can I make it work if I talked to him about it but nothing has changed?