I'm going through this now so I totally know how you feel. I ended a relationship with the man I absolutely thought was the one for me, because he treated me so badly. I still cry every day over him. He hasn't bothered to contact me, he still has my things at his house - it's horrible. It was a complex relationship but none the less this man meant the world to me and I'm totally destroyed.
I can't say anything to help really other than - others feel as you do. You aren't alone. xx
The purpose of life is not to be happy. It is to be useful, to be honorable, to be compassionate, to have it make some difference that you have lived and lived well.