Longtime EX is Connected with Me on ALL Social Media

So I'll try to keep a very long story short.

In my senior year of high school (2006-07) I was with a girl and we were eachothers first boyfriend/girlfriend. Towards the end of the year we split up. We were together almost a year and never had sex (she was a virgin) but did everything else. Bad judgement call on my end we stayed friends, which as a result meant I had to hear about all of her college hookups/relationships. I was essentially her only true male best friend in her college years and shortly thereafter. I was the only guy at her 21st and 22nd birthday. When I moved out of state twice for work she made sure she was the last person to see me. When I moved back she was always the first person I saw. My friends (including some of hers) have said I missed some signals she was sending my way over the years, but oh well.

We haven't seen eachother or talked more than saying "happy birthday" since September 2015. However, despite this we are friends/connected on all of our social media platforms (Facebook, Instagram, Twitter, and Snapchat.) In fact she views/watches about 99% of the stories I post on Instagram/Snapchat. On Facebook/Instagram she will occasionally like whatever I post. The thing is I am the only one of her exes/flings that shes friends with on social media, she has deleted her other exes.

My question is why is this? Is she just doing the ex stalking this? Does she just always want to know about me? Want to stay connected with my life?

Sounds like she could be writing the exact same thing.

Anybody else?

Because we rarely forget about our first true loves and wonder about them.