Wow, so much recognition in all of the replies. I’m not going to start replying to all that because i don’t know where to start.
I’m struggling with that as well, and now trying to learn: what’s wrong with not liking someone? I am not enlightened so i can’t be supposed to be without any preferences. I usually always feel obliged to like everybody and i don’t even know that i don’t like certain people. I want to learn that: who do i like more or less.
And i also would like to learn to be polite and kind to the ones i don’t like, not to let them see that i dislike them, having good functional relations (if necessary)

Of course, like mentioned above, it can be surprising that you happen to like certain people that you didn’t like in the beginning. So it can pay off to try to stay open.