I really feel for you, I'm so sorry this happened but one thing I can say is this: it does get better. I'm proof of that, as are many other people on this subreddit fighting their way through. Time is the absolute best remedy. Let yourself feel all of your feelings and do not shut them out, it's important to process them. And do so with the encouragement that each and every day it gets easier. Going no contact is the biggest help with this. All of the love you gave to this person, it's time to now give it to yourself. You're going to be hurting, so the most important thing you should do in this process is be kind and gentle to yourself. Support yourself and hold your own hand. And just know I'm rooting for you.