The Red Jumpsuit Apparatus - False Pretense Lyrics Meaning

The song is about a betrayal from a close friend, and your view on the world being dramatically changed by it, as supported by the first two lines,

"The world's got a funny way of turning 'round on you
When a friend tries to stab you right in the face"

"Betrayed, but not gonna be willing to change," means how the traitor knows he's hurting his friend, but doesn't think it'll affect him/her as dramatically as it does.

"It's sacrifice" is saying the traitor realizes he's giving up a close friend for his own happiness. "False pretense you'll hurt again," might show some guilt in the traitor.

All along you know you thought you got the best of me
{But} you were wrong and I'm laughing right in your face
I cannot believe you claimed you were my family
Don't sweat it - it's set on false pretense

This shows that the boy/girl's friend got caught before the betrayal went through. This is also supported by the bridge,

"I can't seem to understand it how you turned out to be so cold
You tried but were caught red handed, are you happy with your role?
It's funny to me how you've turned into such a joke... "

The very last two lines give the idea that the two were extremely close friends, instead of just acquaintances, because it says "play the game into my hand," meaning he can predict what his victim will do because he/she knows him very well.