Boyfriend isn’t giving me enough time or attention

My boyfriend hangs out with his gamer friends more than me and he even know it. I see him maybe once a week sometimes not even that. And lately whenever I do see him. I share the day with the guys. Like for example on Friday, he hung out with his friends before I came over and when I left on Saturday, his friends slept over and they’re still there today and it’s Monday night. Or last week we had to push our date to a later time because the guys were coming over. I can never get a day where it’s just me and him. And when he’s with his friends. He hardly texts me and he’s been with them a lot more often the past two months or so but barely gives any time for me. I’ve told him how I felt that he gives more time and attention to his friends than me and he says that’s “he knows, it’s just different with them”. We’ve been dating for almost 3 years and we never really had this problem until this year. It seems like it all started when he turned 21 this year. They’ll either go out to drink or go to his house and play games. It’s honestly pissing me off and he’s not doing anything about it. I get it he has friends but I still exist too you know.