Smile, whether you are correct or incorrect in your assumptions, you are putting an unusual amount of effort into analyzing your ex's motives for logging on or off an app. This is harmful if your goal is to detach and focus on yourself to win her back or to move on. If you can't stop, I would "unfriend" her on that app. I assume there are other channels she could use to reach out to you if she has a chance of heart.
