Is it normal it pains me to be fake?

Man, the right advice is to just be yourself, but I honestly think id be burned at the stake by now if I followed it every moment of my life.

I work from home as a camgirl for this reason and many others. Can't take the fake shit that comes with working with the normal public.

Try to break out of it. Do it gradually if you have to, or all at once if that's easier. I've got a link in my profile saying that living without being yourself is one of the most common regrets people have when they die. No-one likes regret, and the best way to deal with it is by not having any. So be yourself, even if it's difficult at first. I promise it gets easier :)

Say what you think. Always remember that you have value as a human being irrespective of what other people think of you, so don't be afraid to tell people what you think if they don't give you respect for being who you are. They are insecure that they do not have your confidence to be who you are, and that means they might try to undermine you. Don't believe them.

Listen to other people and care about their opinions. But if their opinions are hate, do not allow them to hurt you or make you feel less valuable. You have value as a human being irrespective of what other people think of you, and you don't ever have to take anyone's shit.

Never be afraid to walk away from a shitty life where no-one respects you. Sometimes it takes a lot of changes of scene to find a place where you are accepted for being yourself, but those places are out there for everyone. They probably aren't far geographically. They are new friends and jobs and lifestyles, and shutting out anyone who brings you down.

Mahatma Ghandi: "Happiness is when what you think, what you say, and what you do are in harmony".

I hate situations like that.

I can't even lie and be convincing about it either so I do usually stick to the truth, people have to take it or leave it.

I Can't even play a convincing role of an outgoing, friendly person at job interviews.

Although I know exactly what you are getting at, I think it's a good idea to seperate the notion of a lie with "playing the game." The game being life.
While I believe in honesty and think its the best policy there are situations in life where you have to avoid the truth. It's not lying as such, it's exaggerating optimism and just omitting certain inalienable truths.