That makes no sense. Not even GM get to decide how someone reacts unless it's predetermined and discussed ahead of time. 

I hate people who try to say how someone should do something or shouldn't.
More so, I hate when they get MAD that you call them out on controlling your character.

I once had a guy LITERALLY control my character through an entire conversation without my permission, and when I called him on it, he got defensive. So, I basically told him that if he felt he had the right to play my character, he didn't need me for the RP. 

In some cases, I try to hint at my annoyance of people controlling my character. For instance, if they SAY he she responds to something they say, even if they are correct at guessing the way I would have had her react (rare), I will make them react completely different, hinting in the post that she did NOT react that way. It's my nice way of going; "Please, don't tell me what my char does..."

And I will let it go twice, but if they do it a third time, the hinting even stronger on the second, I call them out.

I have had people say; "If I don't, the RP won't get anywhere!"

Or you could just fucking leave it open for me to fill in when I post... She is MY character. You don't get to say what she does, how she does it, or what she says unless discussed ahead of time.