I feel stuck

So me and my boyfriend will be dating for 2years on September 15 so I’m so in love with this boy I mean so in love from the second I laid my eyes on him I knew he was the one from day one he’s been my best friend.we tell each other everything and our sex life is kinda iffy we were each other’s first and we have only have real sex 3x in those 2 years and it took a year and a half to lose our v cards which I’m not complaining I would have waited until I was dead for him we were just finally ready and we did it but we do other stuff you know sexual but it never feels like he has the energy to get me off like I always end up doing it myself later after we do get done after he’s done I mean but it’s really starting to wear on me I just want to have sex with him not for like to get off just idk how to explain it just to be together sex it more then just getting off you know but the last few weeks a girl came to our school and I know she likes him you can just see it and she told him even though she can clearly always see me and him together like holding hands and kiss that’s type of stuff we he wants to get to know her so bad and I just don’t want to im not a jealous person I’m really not I just don’t have a good feeling about her and he’s been like holding his phone closer to him mot leaving it around like he used to and is just acting weird and I’m really worried he’s gonna like leave me for her even though when I ask he says he would never but I’ve seen to many movies and shows to know saying that don’t mean anything I’m just really worried this man is the man I want to marry and have kids with what do I do? (Im sorry if the grammar is off)