FWB relationship advice 🙈

So I have been hooking up with this guy for 3 months but we've been talking for 5 months. We both are very clear that we dont want a relationship because of where we both are in life. (I just started a time consuming job and hes in med school).

That being said sometimes I feel like he talks to me like we are in a relationship and it makes me feel weird. He calls me "baby", "his cutie", "bb" etc. And hes texted me very often about his "he misses" me when we arent together, that "he thinks about me multiple times a day", "I bring out the best in him", that "he absolutely adores me" and he even said that hes "low key in love with me." (And to have his kids a bunch too) whenever he says things like this I just roll my eyes and say something sarcastic back like hes such a clown or change the topic.

The thing is, that he says these very intimate things and then will ignore me for hours, sometimes days. I dont harrass him with texts at all because I'm not like that but then HES the one who acknowledges that he should answer sooner and keeps apologizing for it. I told him not to worry because I'm not his girlfriend I dont expect that from him which I think made him a bit sad.

Anyways Tuesday he texts me saying he misses me that he wants to talk to me and hear how my weekend was and that he feels bad that hes busy but wants to "dedicate some time for me." Tbh I was really pleased to see the message but I was skeptical. I had a feeling he would flake. And he did. Tuesday night no message. Wednesday night- no message. I havent texted him at all and havent even looked at his insta story which kind of pissed me off. You have time to post on instagram but not shoot a quick text about flaking?

It frustrates me because it makes me feel like hes just a liar and I question everything he ever said to me. It also makes me feel less attracted to him because it's so immature and ingenious. I've been feeling less attracted to him because of this behavior and the last time we hooked up definitely wasnt as good as the other times. So my question is, when he does text me eventually, I know he probably will, what do I do? I dont want to let him see that he pissed me off because I actually think that's what he his aiming for and trying to get me upset but I also dont want him to think it's ok to treat people like this. So ladies, what should I do?