Initial affection always fades away

Hello guys, i need a few opinions regarding a situation i'm currently in, since i have no gay friends with whom i can talk about it.. Everytime i meet a guy that i'm interested in, i tend to develop quite unrealistic feelings that slightly fade away by the time. At the beginning i imagine things like how i would introduce him to my parents, how our life could look together and sort of stuff. Well now there is this guy, which i really like a lot. We are now dating for about a month and met like 5 times. But now, my affection for him slightly fades away and that scares me.. i don't know how it feels to be in love and i don't have much dating experience. He told me that he slept with more than 150 different guys, so compared to him i'm a bloody beginner. Another thing is - we are both bottom. I kind of lied when it came to that term and told him i am both, but honestly i can't really say if that really was a lie. I'm pretty anxious and stressful so i'm afraid to disappoint him when it gets serious after he told me what he is used to. We did not have sex yet because he had a surgery some time ago and did not fully recover from it. He also stated, that he likes to cuddle much more than having sex, which also applies to me. Although he has more experience as i do, he is not really the guy that initiates sexy times. If i meet the right one, should this affaction from the beginning stay..or does it transform into something else? It really scares me and makes me think that i'm not capable of loving someone... One thing i should mention is that i'm on medication right now..i take Finasterid and that probably reduces my libido. I think i will quit or pause taking it because i don't want it to ruin this relationship.. but something is telling me this is not what causes my problem. btw i'm german, i hope my writing is ok.