Confused....!

This is the first time I have posted on the site....not sure why but I guess I was denying the truth about what has happened / is happening to me. I have known my "N" for the past 4 years, all the signs were typical, I was adored, he said "he could so easily fall in love with me", everything revolved around me and he was constantly in contact with me every minute of the day. It felt good, it felt breathtaking and then it all changed 6 months in when he flipped one night (in front of a group of people) calling me a liar and telling me to "f@@k off, I was so stunned I didn't know what had hit me! So time went on and things went from being good (times when he told me he wanted to be the father of my child) to being bad (calling me a stalker, bitch, crazy, bitter, borrowing money)...up and down like a roller coaster. There's been so many hurtful words, telling me I am a liar, saying I would never find anyone in my life, basically making me feel so bad that I learned to not like myself. And now it has happened again, he's just married someone else and has told me I am now nothing to him and he doesn't want anything to do with me. The name calling has been awful, then in other communication he says he wants me in his life, I am just so confused! I need help knowing that it's not just me that he does this to, that I am not the only one!