My new coworker is my childhood best friend/enemy and she is pretending not to know who I am

(this is a repost bc I don't know how to accept the terms of service on r/TrueOffMyChest )

I was best friends with girl (who I'll call Diana) in elementary school. I haven't seen/talked to her in about twelve years and when I walked into my first day at a new job, I immediately recognized her and now she's my new coworker and I'm not sure if I should bring it up.

Basically, Diana and I were inseparable from ages 7-10, until we had a HUGE falling out. Nothing that would actually sound that dramatic now, but in grade school, it felt world-ending. She wanted to social climb and sit at the Cool Lunch Table. This would mean she would have to ditch the weird kid (me) to qualify for the popular group. To do this, she pressured me into writing a bad word and then immediately took my paper and gave it to the teacher to get me in trouble. The teacher pulled me into the hallway and told me to get better friends. Diana's sacrifice had earned her a place at the Cool Lunch Table, but the Cool Kids realized she was also a weird kid with strange interests and kicked her out immediately and she came crawling back to me. Our friendship was never the same after that backstabbing. I switched schools shortly thereafter.

Another incident that may make our professional reunion now a wee bit akward is that I once kissed her. Looking back, this may have been another reason she wanted to switch friend groups as it was probably embarassing for her. She asked how actors in movies could kiss each other. I responded that they either kissed each other normally or perhaps it was a stage kiss. She asked again how actors could bring themselves to kiss their friends. She meant how they could emotionally deal with the embarassment of kissing a stranger or coworker-- this went right over my head and I wrongfully interpreted it as "how do people kiss?" I figured she was just a dumbass and I gave her a demonstration. I grabbed her face and gave her a huge smooch. Diana was of course, pissed off. If she received any bullying for being kissed by the weird girl, I was unaware of it.

Flash forward to this month: I walk into my first day at a new job and Diana's there. We've been making small talk, we get along fine, and it's clear we are both normal well-adjusted adults who aren't the dramatic children we were over a decade ago. The only issue is she is pretending to not know who I am. She introduced herself like we had never met and is continuing this act (is it an act?). I don't know if or how I should mention we know each other without sounding off-putting.

TL;DR I kinda want to bring up the fact that my new coworker and I have history. We were best friends in elementary but had typical child drama. I want a friendly professional relationship with her but I also want to bring up that we know each other