Hi Jakkaru,
What you seem to be saying seems to be something quiet natural called social conditioning, we are all conditioned over time to act and think a certain way and to a certain degree, it seems that you are rebelling inside yourself over this maybe, you can see this way that you have to act around people as fake and annoying, and I think that perhaps you are thinking that you are not developing as an individual person but rather a conditioned person.
The thing is who is being more real, you for recognising this and wanting to just be yourself, or other people for operating like this and not even realising?
People fall into this sheep mentality and become copy cats of others all the time, be it fashion, sport, attitude or whatever, you are recognising that you can be your own person, I guess you sometimes feel this emptyness cus you maybe feel that you are not being all that you can be, or being who you should be.
Also why is it that you feel that you will be rejected if you just be as you are ? sometimes what you think and what people see are two totally different things, we often think the worst on situations by default, sometimes we can try too hard and get into the mindset that anything less will be rejected.
Not one person on earth right now is perfect, we all got our problems and difficulties, strengths and weakness's, we all have good and bad days, happy and sad, strong and weak, no one is consistant in their thinking, we all act to a certain degree, but focussing on these things too much can cause more pain and problems.
What makes you strong, what gives you life, where do you find happiness, what makes you laugh and what makes you smile, what motivates you to do good things, who do you love and why, what do you want to acheive in life, where do you want to be, its healthy to have dreams and try and chase them, try focusing on these things whenever you feel down, you get get great strength and motivation from just changing your thinking to something positive rather than the negative.
I think from reading what you have written so far you seem a strong and clever person, you are seeing life for what it is, sometimes it does seem fake, but dont be discouraged, their is great happiness that can be found in so many things, the trick is to find and chase these things.