How Do I Do This?

I'm a cheater.

If you ask my SO's family, it wasn't cheating because technically I broke it off.

Here's the story. So my ex fiance, well call him Controlling Maniac (CM for short because it sound like cervical mucus and that's basically what he was)

CM moved away to Job Corps. CM never wanted me to express myself, had to listen to his music, never get tattoos, dye my hair black, keep it long, take out my lip ring, etc whole 9 yards.

So since he was gone I started doing shit. He didn't see me every day so I got purple hair, cut it short, etc.

CM was mad so CM wanted me to move up to Syracuse NY in December and stop contacting my family.

So in October CM and I fought over the phone I told him I needed a break from his controlling demeanor.

Now I already had a crush on my Buddy... well call him BB for big butt.

I already felt like I was over CM I just was to afraid to call it quits. BB came over to my house with two bottles of Jack, Keystone, and some coke. BB and I were celebrating my friend's birthday. So CM was calling over and over and BB and I got drunk. And we hooked up. BB and I were really drunk. BB woke up the next day laying on the floor with his boxers on. So BB and I started talking after the hangovers were nursed and he kept saying "CM is your fiance and I didn't mean to have my feelings come out" but like I said I had no feelings but hate for CM by now because he was trying to take me from the family.

So I broke up with CM completely.

Confessed my feelings for BB and now BB and I are happy happy at almost March.

Except CM just messaged me about him graduating and wanting me there.

Part of me wants to show up in Syracuse just because I know I don't wanna seem like a bitch but I don't want to see CM again because he was so controlling I fear he may try something.

What would you do? Do I tell CM to go fuck a duck or take a plane cross country for a graduation while taking BB with me to show support?

My friends all say go because CM and I were good friends before the relationship. My BB says I shouldn't be so hard on my ex despite everything because dwelling on past can hurt. But my insides say CM may try and hurt BB and/or me.

PS we are all adults here. I knew it sounds like a kid issue but yeah