Search Results: girlfriend talks to an ex

I went out a few times with my coworker in 2015. As promising as the relationship was, I broke it off because I didn't feel I was ready for a new relationship, because I wasn't over my first girlfriend, even though we broke up a year prior.
It became an easier decision when she told me she still lived with her ex. But she made it awkward as hell at work. But she quit a few months later.
Fast forward to June 2016, she comes back to work and she holds a grudge against me. Especially since I got back together with my original girlfriend.
I left in August of 2016 and in in December of 2016, my girlfriend and I were having issues and the co-worker called me up one night, and asked if I'd hang out and have sex with her before she moved home the next day. Even though my girlfriend was leaving for a mission and our breakup was inevitable, I didn't do it.
But in early 2017, the co-worker and I started talking regularly and talked about everything that happened. But then she started trying to convert me to the Mormon church and that was the same religion my ex was a part of and I wasn't Mormon.
I blocked and didn't say absolutely anything to the co-worker from that point on.
Last year, I made a new Facebook, and the co-worker never came up during that time.
Last night, I had this very unusual dream where I met up with the co-worker and we worked things out and all that.
Today, I'm on Facebook and she came up as a friend suggestion, with 0 mutual friends and I used a new email and no phone number when I made this Facebook. In addition to that, all I have to do is type 'n' and she is the first result on my search and I never searched her once.
Like I said, it's been almost two years since we last spoke and she hasn't come up whatsoever in this Facebook 8n the year I've had it.

This has really thrown me for a loop and I haven't even thought about her since we stopped talking.

Is this a coincidence or more than that?

After 4 years if dating and 7 months engaged my girlfriend broke up with me because she didn't feel like we'd make it with our religious differences. It was an extremely difficult breakup and it devastated me.
Within 8 months she married a member of her church.
It's now been 6 months since she got married, and I got a call from her work. We used to work together when we first me and I know her boss. He called me about some kind of situation, no specifics, and asked me to come down to the workplace and talk.
I arrive, and I get escorted to his office where my ex was waiting and half of her face was beaten up, along with some cuts and bruises on her arms. Apparently she got into a fight with her husband and that was the result.
She had asked for me to come down because she wanted someone she trusted to come with her to collect some things from her house.
I argued that she had her family and friends in town and her parents were a few hour plane ride away.
Her boss insisted and asked again if I would help her and she was in more tears at this point. I told him that we weren't together anymore, I didn't want to get involved. It at that point was a police issue and she had plenty of people to help her. He said he understood my side of things, and I excused myself.
My ex got up and grabbed my arm and asked me again to help her and she was completely hysterical at this point.
I tried to be calm and tell her she didn't need my help and she had plenty of family and friends to help and I walked off.

Her boss texted me later and said he wasn't upset with me, and understood why I didn't help.

Why was I called and should I have helped her?