I need advice, ladies please help... No hate please I’m already upset

My boyfriend said that he feels like we’re “drifting apart”. what can I do to fix this I don’t feel this way but we’ve been together 3 years and he feels this way please no hate in the comments or telling me to move on I love him and want to be together and fix this is it possible please give me advice and help and positive thoughts..

I’m 18 & he’s also 18, turning 19 both of us in 20 days. We are comfortable with each other very and see each other practically every day so maybe we need space apart ? I don’t know... he says he doesn’t know why the reason is that we’re “drifting apart” but he does think we are and it seems to me like he doesn’t even care and this is basically the end of us.. we’ve been very serious no cheating or anything for 3 years practically living together and seeing each other almost daily and very comfortable telling each other and showing each other all of us and not being afraid to tell each other anything... I really don’t want to end things and I barely even feel like we’re “drifting apart” just maybe that I don’t feel so “In love” anymore like when you first start dating someone & falling “in love” when you get butterflies and etc. we’ve been fine lately eating out together so much, sleeping over each other’s houses, going doing things every weekend, we were just at my grandparents last weekend, always doing things with his parents & siblings all of us... etc etc I don’t know why things randomly got messed up last night after I mentioned to him that I felt like things are weird like somethings wrong with him or there’s something he wants to say... today he had off of work & we have barely spoke (texted) or anything and I’m lonely and sad I just want things to be okay again.... we only texted a little this morning, him saying he isn’t happy right now and doesn’t want to see me and “fake an emotion that he’s happy, and act like things are okay because they aren’t okay”.

This all makes me sad because I have no friends to go see to cheer up or anyone to even talk to about this girl to girl for advice and to feel better about venting and I have no clue what he’s even doing right now currently and I ended up doing nothing today. Anyways ladies please help with any advice and whether you think we can fix this and if so what to do about “drifting apart” what can I do... I really want to be together and have a happy, healthy relationship... I’ve asked what I can do to make him happier if there’s something he wants to do maybe not involving me like more alone time idk.. I feel like he’s starting to not care anymore if we are together or not and it hurts a lot. Please comment & thank you for reading this. 💕 going on anon because I’m shy & embarrassed by this, but I’ll most likely reply to comments. 💕