Why woman can be so mean to each other?

I like to watch a chubby girl streamer at night, she is really a good person and really smart. She looks after her body and talks about living healthy, she even has a small girl crush on me which is really nice, I like to imagine that I am her crush. She has a great sense of humor and I really enjoy watching her.<br><br>But why I ask myself why woman can be so damn mean to each other, I have seen all the mean comments she gets and it's really sad and hurtful to see it. Like woman should support woman and girl should support girl but they don't, they get mean and nasty to each other and it's really a shame.