How do people learn to move forward after such a heart break?

I followed a girl to a new town and obviously we didn’t work out. We grew apart and ended it amicably. We’re currently still living together and I’m moving back home at the end of the semester this December. I’m stuck and I can’t seem to move forward, I’m split in two over this. Logically, my mind can understand this and I feel like my mind started the healing process the night we cried together over this. Emotionally, my heart cannot fathom existence with anyone else. I don’t mean to sound sexist with this statement, I look at other women and talk to other women but I just can’t seem to find them desirable. Granted–I am not saying they are ugly in any way whatsoever. When I say “desirable” I mean that I cannot see myself with them. I feel like she isn’t the one for me and vice versa. I feel like my ex was my cliche “perfect mold” who fit everything I ever wanted and will ever want in another woman. That is my problem. I try so hard to get my heart to understand that she isn’t the only person in this wonderful world. I try so hard to picture happiness in something else but it just doesn’t happen. It’s like I’m locked in an opaque box and I know a better world is outside of it, but I just can’t see through the haze and smoke to fully wrap my mind and heart around the possibility of bigger and better things out there. She was my first in every way possible and I will never forget her. I know I’ll find repose in new ways, but right now that seems impossible. The reason I’m not trying to win her back is because I feel guilty because in my mind I’m thinking “You don’t know what you have until it’s gone.” She was the first person I loved the way I did, but in the back of my mind I felt like maybe we just weren’t meant to be. Not because something bad happened between us, but because we just eventually grew apart and started wanting different things in life. To make a long story short, I feel like my wound is stuck in the past tense and wont heal for the future. I know I wont be ready for another relationship for a very long time. I just want to know how to overcome this slowly but surely. I’m stuck.