My [21F] boyfriend [24M] hardly wants to have sleepovers anymore

When we first started dating, I’d sleep over at his place 3-5 times/week. We go to the same university and started class at the same time, so it was partly out of convenience I’d stay over so often. We’re almost 8 months in now, and I’ve noticed the frequency I sleep over has decreased. (Maximum 3 nights/week) He’s cancelled sleepover plans with me day of, even right before he was supposed to pick me up, saying he was just too tired, but we don’t do a whole lot when I’m over there. I would be completely content just going right to sleep and he knows that. When I bring up the fact that we don’t see eachother as often, he responds with “I just like time to myself” which I understand to some degree, I like time to myself as well, but I don’t like going days without seeing him, and begin to feel lonely. Am I being too clingy? I wonder if it’s partly because it’s summertime and we’re not going to classes right now, but I also feel like I’m doing something wrong, or he’s tired of me or something. I know his roommate isn’t a huge fan of me as she’s said disrespectful things about me to him in the past, so I wonder if she’s asked him to cut down the nights with me, but I don’t want to sound insecure asking if that’s the reason.

I guess what I’m really asking is, has anyone else ever been on either side of a similar situation? As time goes on, have you wanted to spend fewer nights with your partner? I understand that the beginning of a relationship includes the honeymoon phase and stuff, but I don’t think that becoming more comfortable in your relationship means you want to spend less time with them?

TLDR: is it normal to want to spend less time/fewer nights with your partner as time goes on? (No apparent reason I can think of)