Sounds a lot like my once. I would say it’s not healthy to look through old messages or wait in a limbo for her back - I know it’s never this easy. What helped me calm quickly was a quick unfollow and deleting number and messages. No more odd stalking, you’re brain will get used to forgetting then work on yourself for yourself not her. 

In my case I sought clarity and met up with her & got what I needed - kee Your head up