I know its coming from a good place, but that is a crap thing to say. "life is too short to waste time hating people" no. life is however you want to spend it. If you want to work a career, good for you, I'm sure you'll be successful. If you want to play video games all day, fine, I'm sure you'll enjoy yourself. If you want to love everyone and try to actively ignore people (which takes effort), then that's fine, you're free to do that. But you're also free to hate people too.

Hating someone doesn't take some insane effort, and it's perfectly fine to do. The whole "Love the world, and hold hands" thing is ridiculous, because you can't be friends with everyone. I hate my neighbour because of the things he's done to me over the years, and that is perfectly fine. I'm allowed to do that, it doesn't take away from my life or anything.

You can't be judgy and try control other peoples lives and tell them not to feel valid real feelings. To anyone else, go around hating people if you want. you're human and no life is not too short, it's the longest thing we have.