My boyfriend is acting different HELP

Me and my boyfriend have been together for 2 years and 2 months. We have been happy and healthy for the whole time except recently. Recently he has been going out with the ‘boys from work’ more often than usual and when he comes home he acts as if he’d rather be back out than with me. He’s happy with me and treats me right until he goes out with those, as soon as they phone him, play online games with him, or goes out to meet them he always comes back different I don’t know how else to describe it.

I also used to sometimes go out with him and them all when his friend Callum was bringing his girlfriend Hollie. But lately even if others girlfriends are there he doesn’t want me around his friends, he asked me to remove a few off Facebook just before this behaviour started it’s as if he doesn’t want me to be around them anymore.

The other night he promised he’d be back around 10:30pm so we could watch a movie together he didn’t return any of my calls and eventually came home at 12am.

I love him so much but what do you guys think??