The guy I...like? Maybe?

There’s this guy I’ve like since I was literally 13 and now that I’m older I like him even more, like the idea of having kids and a future and a life with him sounds like the best thing in the world, getting married to him sounds so amazing but I swear to you, when I think about anything more sexual than handholding and kissing I cringe. I can not stand the idea. I’m not sure if it’s because he’s so much bigger than I am? I’m 150 lbs and he’s literally obsessed with the gym and is Atleast 275. Help!!