Best friend in the world doesn't tell me she's in town after moving

Sorry it's long but need help. Okay so in 6th grade there was this new girl and me and her instantly clicked we were best friends, we were super close, teachers would call us Siamese twins because we were always laughing and together, our parents were friends it was great. We were all each other had in school, it was just us and we were perfectly happy with that. Then at the end of 7th grade she moved. It sucked super bad. I tried keeping in touch with her, asking how she was letting her know what was going on with our exs and myself etc, but she rarely ever responded. Idk why, I mean we were close believe me I wasn't some clingy friend that she secrectly didn't like if that's what it sounds like. Anyway Were about to be seniors in high school and a lonnnnng time ago I finally gave up trying to talk with her. But we still like each other's instagram posts and stuff. And today I saw on her Snapchat story she was hanging out with my current kinda close friend -yet she hated her back then- so I'm just thinking like really? What is up?? She posted on her instagram she'll be in town and to message her if we wanna hang, but that was after her and my friend were together. I mean I moved on I found the bestest friend ever, but I mean I just feel crappy, like why didn't she ever message me back or tell me she was going to be in town, idk I kinda wanna she her -bc I mean we were each others first best friend and we have so much great memories together- but I haven't seen her or talked to her in like 5years so I kinda don't even want to see her. Idk what do you think? Should I just message her and hang out bc she leaves or does it sound like she doesn't want to see me? If I were the one to move I would of told her asap that I was in town but she didn't so idk anymore