The most likely reason for the hostility that you are seen is that her reactions to Ron don't seem normal, in the first chapter you have her saying that she goes from geeling little, to just being soaked whenever he touches her. And while this does not autimatically mean Love potion, it doesn't seem a natural responce.
Another reason might be that most people that aren't hardcore canon shippers started to dislike Ron/Herm after book 7 (it ruined alot of things in the series), and thus you are catching flak for having that be one pairing (despite it not going to last).