Someone told me a long time ago that I have a right to my feelings. I think that's true for everyone & especially in this case! You have a right to whatever emotions are stirred up in you without having to think of it as 'over-reacting'.

Maybe look for patterns? If this is a pattern of reactions with interactions (or potential interactions) with her, than maybe it's time to reconsider the type of friendship you have.

I hope you're doing better & good luck to you.