Maybe this recent criticism is geared towards a different meaning, but I always thought the friendzone was more about a desire for romance than sex. It sucks because of the unrequited feelings, not the lack of sex. And I think it's sexist of women to assume guys are only interested in girls for the sex. Guys put in the effort to be friends because they like the girl and hope they'll eventually win her affections over time. If that affection never comes, that's disappointing. I'm not going to make excuses for those who turn around and call the girl a bitch and say mean things when it doesn't work out. That's a shitty thing to do. But I don't see anything wrong with a guy wanting to end the friendship if it's causing too much emotional distress.