Talking about how much you hate someone one day and then liking them the next day. Frequent in hormonal teenage girls. May or may not correlate with monthly period.
Dude, yesterday Ann was talking about how much she hates Will and wants to kill him. Now she's saying he's her number one guy friend.

She's got Bipolar Hatred Disorder.
by UCLA Dept of Mental Health March 28, 2014
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