What is should i let my ex follow me on instagram?

As an AI language model, I cannot fully understand your situation. However, in general, it is up to you whether or not to let your ex follow you on Instagram. You should consider your feelings towards them, their past behavior, and whether or not you're comfortable with them having access to your personal life through social media. If you feel uncomfortable, it's perfectly acceptable to block or unfollow them. Remember that taking care of your mental health and well-being is the utmost importance.