<human>: Can you give me the gist of the text in a nutshell?

I dated this guy for 14 months. Expressed my love and loved him unconditionally. There were absolutely no boundaries with him. He was my everything and I cared so deeply I was willing to put my reservations aside for him. He started establishing contact with the "abusive" ex gf (21f). First with a chaperone, an hour a week. Flash forward a month and no chaperone, (4+ hours a week), sometimes taking her car. Despite my reservations, he insisted I was over rationalizing. He cheated on me with her. They had been dating for "quite some time" but "they" didn't want to break up with me because of "how I would react". All I feel is betrayal. Regardless of the legal drama because of him threatening me, it all still hurts. He talked to me for two weeks after the break up. Kissed me even. Told me we'd be back together and that he'd never be with her again. How do you spend 14 months with somebody and not even know them? I knew he was too good to be true. Hell, just a week before we broke up we were talking about our wedding. All the while he was seeing her and making plans to move in with her. It hurts more tha anything I could ever describe. How do you just "get over" cheating?
<bot>: exbf, love of my life cheated on me with a girl that abused him and he swore would never get back with, we were talking about reconciliation, all the while he was seeing her. How do I get over it?