If you think about it, you do know the people in your life who really like you. People who hate you will actually be nicer to you! For example, if you work with someone who really doesn't like you, and they don't want you to know it, they'll pour the bullshit on a little more. It's like "Hey! Did you get a hair cut? ... You look good! ... You look sharp!". They will always over compensate!
If you think about the people you secretly hate, but they don't know you hate them, you work a little harder. If someone you didn't like that much gave you a call and said "Hey, you want to grab some lunch Wednesday?" You wouldn't be short with them and say "Nah! I don't think so, I'm pretty busy, we'll do it some other time!" and hang up! On the contrary, you would say "Do you know what?... Normally, I would love too!... I would absolutely love too!!... I mean it would be awesome!!!... but this Wednesday I can't, I'm so sorry!" Compare that with someone you just know, are just friendly with or just like. If they called and said "How about Wednesday?" You would just say "Wednesday's not good for me, I'll give ya' a buzz." You automatically over compensate when you don't like people because you don't want them to find out about it.
So next time when someone is too nice to you, know that person hates your fucking guts!