Is it normal to suddenly hate someone who is interested in you?

No one could possibly know for sure if your emotional reaction to someone openly displaying or addressing their fondness for you is 'normal' or not. Reason being is we don't have any idea of your background beyond you stating that you have had a 'stable upbringing'.

But if by stable you mean you didn't have any issues growing up in regard to relationships then I might attribute your disgust of newly anointed crushes as simply your lack of understanding of what comes from a new relationship. You probably find yourself floating around at gatherings, with many acquaintances that you socialize with, but probably few close friends that you trust. There's nothing wrong with that, there are plenty of women like you 'social butterflies'. You simply do not find upfront emotion like these guys very attractive. I bet people who you have casually met go farther, perhaps because you feel more like a peer and less like a women on a pedestal. Or maybe you just like the chase a bit more. Either way, you're perfectly normal. Get out there and date, let the weepy guys find someone else. :)

Im kind of the same except i dont get sick or anything i just play along until they get the courage to ask and i get to say no lol
it maybe sad but then again i try do good and no one gives a shit.

At least you don't take advantage of their feelings and try it on for size just for kicks. There's many people out there who would!!! A smidgen more compassion from you wouldn't go amiss though!! It takes balls to tell someone you like them!! Be flattered! Let them down gently and if you genuinely like them as a person stay friends. But don't whatever you do sleep with them!!! That is a surefire recipe for disaster!

I once did that. And I regretted it. It happened when I was in seventh grade. This boy was one of my close friends. One day he passed me a note, saying that he liked me. At first I laughed it off cause I thought it was just one of his jokes. When he said he seriously liked me, I was suddenly apalled. My attitude turned 180 degree from friendly to hateful toward him. At the time, I kinda felt 'betrayed'. I trusted him as a friend but he then wanted more.
It's been nine years and I'm in college now. A few months ago I bumped into him and found out that he's also attending my university. He OBVIOUSLY saw me but avoided me all the way. That's when I realized how much pain I've caused him EVEN THOUGH it happened when we were still kids. I've been trying to look for him ever since. I've contacted old friends from junior high to find out if they know how to get in touch with him but to no avail. I'm still trying now. I have to apologize to him.
My point is you'll never know what damage you'll cause to others by turning from a happy-go-lucky friend into murderous, rabid enemy. You might regret it like I do now. If you don't return their feelings, try a subtle way to reject. Talk it out. It'll make a BIG difference.
Hope that helps.. =)

all i can tell you is a quote i heard(allthought i think only the first part aplies to u)
"We ignore those who adore us and adore those who ignore us"

Thats normal. I dont think anyone likes me, i act in a way that makes people not like like me like that. But if they did i would do the same then id avoid them and feel bad about it but still feel sickened.

I think during the process of your friendship you might be sending signals that encourages the person to like you more than a friend Example hugging and testing the person all the time.

I don't think that is considered normal. It would depend on how you feel about that person. You said that you had never dated nor are interested, that could have something to do with why you feel that way. You might fear something new/different from what you know and, when you realize it doesn't interest you, you react negatively towards it.