Because it's annoying, that's why.

[ And she's stressed; she needs to take her stress out on someone. ]

Besides, it's healthy to take things out on other people every now and again. [ According to the internet. ] And I only plan on disappearing if both of us get our memories back, hopefully.

[ Depending on what those memories are, exactly. She's thinking that some of them are not going to be very pretty. ]