Really need advice on how to get other this feeling. Because this situation has awakened the deepest obsession and feelings of abandonment I have ever experienced.

I kicked my ex out of my apartment last week; the relationship was toxic and I wasn't happy but I truly did love him and it just seems he really only used me for a place to live and an excuse to relapse and start drinking again. I know I shouldn't miss him, but I do. 

I did not handle the breakup gracefully. After finding out he lied to me about another female he was messaging and cheating me out of half my rent money.. BPD rage got the best of me and I contacted his mom, hacked his social media accounts, messaged his ex as if I were him.. not my proudest moment and I'm very embarrassed but I was so angry, it consumed me and I know what I did was not okay and I made myself look insane.

But since the breakup- he's re-followed the ex he swore up and down he was over because of how terrible their relationship was, blocked me on EVERYTHING, and just completely erased me from his life.. he was still staying with me a few days after I kicked him out because I was allowing him time to find another place to go so he wouldn't just be on the street and even then, with me STILL helping him, he acted so cold and uninterested in me.. like his feelings changed in the matter of a night. 

I KNOW this isn't a me thing, but it's made me feel so easy to be unloved and so easy to be forgotten.. and I did EVERYTHING and then some for this person because I loved them and still do.. did I cause him to ice me as cold as he did or am I just THAT easy to forget..