Do I stay or go? (LONG)

I just wanted to get it off my chest because I don't talk about it at all and I'm pmsing right now so I'm in my feelings..so I'm in a relationship w someone I've known for a really long time. We were fwbs but earlier this year we fell in love and now we both are really happy. Things have been amazing. There's a huge problem though.

For a while he's talked about moving to a different state. And it's really far. Opposite side of the country far. But he doesn't like it here and never has. And he feels that there will be better opportunities for him if he moves.

When he first told me he wanted to move it made me sad but I didn't say anything because we were only sleeping together at the time and i felt that my input wouldn't make a difference at all. But he's been a really good friend and I had grown feelings for him then. He was planning to leave in the summer but shit happened and he's still here. And before the summer started was when we confessed our feelings. We got really close and our relationship got stronger. But him moving away is still something he wants to do.

Ever since we became serious, he's talked about it way less, but I still knew he wanted to move. It was really upsetting to think about or talk about it because I fell in love w him and we both knew that if he left a LDR just wouldnt work and we'd have to break up.

The other day he asked if I would go and move away w him. I'm in my last year of school right now so he said that he would leave before the year ends and when I'm done w school and when hes settled in I can move in w him. He used to ask me to go w him in the past but I told him no because things werent serious then. But now it is and the idea of him leaving breaks my heart. And idk if I would go. Mainly because the state he wants to move to is sooo far. I like it here, and everything and everyone I know is here. But he is beyond important to me. He's more than just my boyfriend. Hes my best, closest friend. Hes the only person I can truly open up to and be myself around. He's always there for me no matter what. He'll sense that im upset and he'll drop everything to make sure im ok. Even before we got together he's been my most favorite person that I could trust w anything.

I dont know what to do. If I dont go, he'll leave, we'll split, and I'll be here crying myself to sleep every night wondering what if. Because I do see a future w him. I see us getting a place together, getting a dog, getting married, and maybe even starting a family. I dont want to make a mistake and say no to something that could really make me happy. On the other hand, if I leave, I'll only be doing it to be w him. I'll have to adapt to a completely different environment, different people, and be really far away from my family and friends. (The same will happen to him as well, the difference is that he likes new experiences and I like things staying consistent.) I don't wanna end up in a place where I'm miserable and alone.

I do see myself leaving to be with him and being really happy. I guess it's overwhelming because it's so far.

I try to think about it realistically and I can see myself moving with him. We never fight, we always communicate, and we've always worked really well together. Our personalities are so different and that's brought out better sides of ourselves. And I see myself growing old w him. Were young (21) so i dont want to sound like I'm just this naive young girl who's in love, but I cant explain it. I've never felt so sure about something, let alone someone. I've just been very paranoid about being scared to move because I wont like it, or something terrible would happen.

I've never asked him to just not go. I'm not gonna do that. This is something that hes wanted for a long time. The fact that he wants me to go with him means alot. I'm just really unsure what to do at this point.

Idk. That's just what's been on my mind.