FWIW I have been through something very similar.
It does get better in the end and one day you will be glad that this finished and only sorry that you wasted time after it ended.My stages were...
numb, crying, desperately needing him to comfort me (but knowing he couldn't because he was the one who had hurt me), getting my hair cut, feeling awful when he was cold to me, feeling like it was worse than my father's death, calling him too often, obsessing about the OW, wanting to make him regret it, wanting him back, trying to make him jealous, boring people talking about him.
Along the way, I learned to do all the things that I thought were beyond me. Mostly I learned because I was so low that i didn't care what happened to me so I just did the jobs because nothing could feel worse than how I was feeling anyway. Then suddenly I realised I'd learned how to do a whole load of new things and I began to feel a little better.
Also, i lost all the excess flab.
Then people started to offer me friendship and I started to have a social life again.
Then he hit me and I was knocked very low again. But this time, I realised - finally - how horrible he was.
Then I dated someone else and even though it didn't last long, I realised that there are better men out there.
Then my career started to take off (because I'd had time to invested time in it).
Then I met DH.
Then I got pregnant. One day when I was about six months into the pregnancy, I saw the ex-BF in the street as I was coming home from work. He wasn't even worth crossing the street to say hello to. I just really wasn't interested enough to pass the time of day with him.
My only regret is that it took me a year to get over him. It was a wasted year. he wasn't worth the relationship, never mind the year of mourning. The sooner you can get to that stage, the better for you.
Please don't call him or risk your happiness by asking him to come back. This will work out for you.