He sounds quite controlling & possessive.
Its ok for him to enjoy himself with his mates? but you have to play the dutiful gf and stay at home looking after the little one.
If your not happy in a relationship, you really need to sit down with each other and talk things through, if he dosen't want to do this, you may well have to give him an ultimatum.
Far to many people get into relationships then realise that that person did not live up to the expectations you wanted them to, he has an equal responsibility to raise your child like you, your entitled to have a social life even if it means going out just with the girls.
If he goes out, tell him your mum will look after the baby and your go out with your friends, lets see how he reacts to that.
Only you know if you've made the right decision to stay with him, Do not let him keep your relationship together just because you have a baby, you will not be the first or last person to bring a baby up on your own.
Sit down and talk {can't beat it}, and don't be afraid to tell him your ''true feelings''
All the best