Beware of Prince Charming

We met five years ago through a mutual friend. At first we would only hang out in a group setting with some flirting but I never really thought of him as someone I would date. It all started one day when I received a friend request and a private message leading us to exchange numbers (this was the day he decided that he wanted me). He started texting me every day telling me how beautiful I was and how he thought we would be perfect together just flowering me with compliments but was also fishing for compliments in return. FIRST RED FLAG. The first three months were very very intense. It only took a month before he told me he loved me, how he never had feelings this strong, and thought I could be "the one". He was funny, witty, charming, and very affectionate. I was hooked! Then as things started to get more serious I started to expect more from the relationship so he started to distance acting more casual toward me, texted me every few days instead of everyday, restricted his Facebook, seeing him was like pulling teeth. He would use excuses like "I'm sick" or "I didn't feel like talking to anyone today". I couldn't understand the complete 180 in his behavior so I started questioning him only to make him more moody and agitated leading me to believe that I was annoying. If I were upset about something he would ignore me for days instead of discussing it then casually text me days later. RED FLAD NÚMERO DOS. He didn't like when things were "complicated". At this point I was in so deep I was consumed by him and wanted him in my life so I did what any other naive girl would do accepted the situation. Until one day he stopped responding to me all together. After a few weeks of badgering him and demanding an explanation he finally responded that his life had been crazy and he needed time to focus on himself for awhile but that he still cared about me. RED FLAG THREE. I was devastated. We went several months without any contact then he slowly started commenting to me on FB which eventually led to texting telling me he missed me. I was on cloud nine thinking he really does love me after all but it turned out he loved the power he had over me. Most likely during that time apart he was working someone new and it failed ( I realize this now). So anyway, it was like a washed up version of stage one all over again. One day he left his Facebook open on my lap top and I saw him flirting with another girl when I confronted him he got very defensive and said "I can talk to whoever I want". I knew I couldn't trust him and in the back of my mind I was afraid he would start ignoring me again so I irrationally told him we should stay just friends. I couldn't take the emotional stress but I still craved for him. A month later he was in a relationship with the same girl I confronted him about (Her and I share the same mutual friends with him). He convinced me that him and I were still good friends and continued to feed me crumbs of attention keeping me on the back burner. After about four months (assuming the honey moon stage with her was coming to an end) he started coming on really strong telling me he missed me and that he still loved me (I allowed him to suck me back in emotionally). It turned into a messy love triangle and to this day the other girl has no clue about it. Here's the kicker...her and I are now friends. A year into his relationship with her (the same time it took him to discard me the first time). I found out he had did the same exact thing to her and ignored her for months before he broke up with her while he was busy flirting with me. At this point he was full force love bombing me again. I knew his game but somehow still got sucked back in for a third time. It was like I was addicted to the pain of wanting someone so unattainable. I wanted to be that girl to "fix him"! It was like he was my drug. I found myself chasing him, not caring if he was talking to other girls as long as I had him too, letting him take full advantage of me. It was an up and down emotional roller coaster. I would get upset and say we were just friends...he would lure me back in....I would end things...he would lure me back in by telling me I was "the only one he loved". This went mostly on the DL. I gave him exactly what he wanted: attention, sexual desires, admiration without commitment, pressure, or as he called it "drama". A few months ago I was at dinner with one of our mutual friends and also "the other girl" who happened to casually bring up how he had been in contact with her telling her pretty much the same lines he was feeding me. I almost chocked on my wine. My first instinct was to confront him. I was about 3 wines deep so let's just say the first text wasn't very pleasant. We argued back and forth a few times with him pretty much defending his actions by saying "You bring drama, this is ridiculous, I'm only being nice to her, I can talk to whoever I want whenever I want". As for me I got so fed up I called him out on all his games and threatened to tell the other girl the truth in which he manipulated me by saying "you will only hurt her and that will say a lot about your character". ( Classic N if I don't say so myself) His final text to me was "I'm done with this, goodbye." Placing the blame on me which ironically compelled me to reach out to him a few more times to reconcile. I got no responses except for an indirect Facebook status implying that I am toxic and he is done with my games forever lol. I have seen him twice in group settings with mutual friends both times he ignored both me and "the other girl" acting as if we both didn't exist. Her even more devastated than me because she has no clue of any of this because I never found the guts to tell her with fear it will ruin our new friendship. This was when I was made aware of the extent of Narcissistic Personality Disorder and at first felt much relief. What bothers me the most is his hatred toward me as if I murdered his family. All I was looking to do was to make peace with him so it wouldn't be awkward when we saw each other at group events and he chooses to stay bitter. It has been almost 3 months since he said "goodbye". Now that I am aware of NPD I am ready to move on once and for all. Do I miss him? Yes. Will I ever allow myself to be a part of such a dysfunctional, unhealthy relationship with him again, no. Do I ever tell the other girl? What if he tries luring her back in? One of our mutual friends does not think I should tell her....