Dreaming of him (alot) 💔

So, i've been dreaming about this guy tht i blew my shot with (alot).. we knew each other since the 7th grade & i liked him ever since the first time tht i saw him & i thought, wow i'm gonna marry him one day, but i dont really know when he started liking me tho ? Anyway, we became friends then we became best friends & we would be flirting with each other alot tho & a part of me thought tht it didnt really mean anything because were just really good friends who can joke around bout stuff like tht, then another part of me was thinking tht maybe it kinda meant something. After 10th grade he messaged me saying tht he misses me & i told him tht i missed him too, then he asked me if he could ask me a question & stupid 16 year old me thought he was gonna ask an inappropiate queation, so i just said "oh, i dont like those kinds of questions". He said tht he was sorry & then tht was kinda it. We havent talked in like 6 years (if tht), but last year was the 1st time in like what feels like forever tht i talked to him.. i sent him a really long note confessing my feelings towards him & everything, but he messaged me back saying "Listen tht was a long time ago, no hard feelings and i would appreatriate it if you didnt send me anything like this again because i have a girlfriend tht i love very very much" & whatever else he said. I then said oh, sorry.. he said tht i was fine, then i said ok & then tht was it between me and him. But his girlfriend started messaging me & then we kinda got into it, then she blocked me off of his thing. Not long after tht happened, one of my other friends said tht he was single now & i asked what happened & they said tht they didnt know, so i said oh, well. But now hes back together with her. Tht was really humiliating & i have no idea why i even did it? I obvisouly feel bad for everything, but i kinda forgave myself which thts all you really can do you know. Its just tht im kinda tired of constintly thinking about him/dreaming about him since you know he made his feelings about me pretty clear, so idk why i still am ?!?! Oh, also while she was messaging me she said something about him wanting to propose to me back then & i was just thinking yeah, i highly doubt tht he was gonna propose to me, but you never know, like maybe he was, but either way i would've said yes to him. I moved too & like i didnt tell him tht i was or told him bye or anything (yeah, i was dumb) 🙄. But like i wanted to ask him out quite a few times, but everytime i worked up the nerves too, it'll be to late & he already had a girlfriend, but i held my tongue because you know he was my best friend and i respected tht, & he didnt say anything either whenever i got boyfriends.. so idk why i did what i did ? And i mean i still respect tht & he does seem happy so i guess im happy for him tho, but like i do miss him & sometimes i just cry over nothing but in the back of my mind i think tht its not just over nothing.. i think its just because i miss my bestfriend you know. But can anybody tell me why? P.s. im sorry tht this post was long, i wasnt really trying to make it long at all. Also please no bad comments.. i already feel stupid 😭