[Verse 1]
I should've known by the way you passed me by
There was something in your eyes, and it wasn't right
I should've walked, but I never had the chance
Everything got out of hand, and I let it slide

[Pre-Chorus 1]
Now I only have myself to blame
For falling for your stupid games
I wish my life could be the way
It was before I saw your face

[Chorus]
You stole my happy, you made me cry
Took the lonely and took me for a ride
And I wanna uh-uh-uh-uh-uh-undo it
You had my heart, now, I want it back
I'm starting to see everything you lack
Boy, you blew it, you put me through it
I wanna uh-uh-uh-uh-uh-undo it

[Post-Chorus]
Na, na, na, na, na
Na, na, na, na, na
Na, na, na, na, na, na
[Verse 2]
Now your photos don't have a picture frame
And I never say your name, and I never will
And all your things, well, I threw 'em in the trash
And I'm not even sad

[Pre-Chorus 2]
Now you only have yourself to blame
For playing all those stupid games
You're always gonna be the same
Oh no, you'll never change

[Chorus]
You stole my happy, you made me cry
Took the lonely and took me for a ride
And I wanna uh-uh-uh-uh-uh-undo it
You had my heart, now, I want it back
I'm starting to see everything you lack
Boy, you blew it, you put me through it
I wanna uh-uh-uh-uh-uh-undo it

[Post-Chorus]
Na, na, na, na, na
Na, na, na, na, na
Na, na, na, na, na na
[Bridge]
You want my future, you can't have it
I'm still trying to erase you from my past
I need you gone so fast

[Chorus]
You stole my happy, you made me cry
Took the lonely and took me for a ride
And I wanna uh-uh-uh-uh-uh-undo it
You had my heart, now, I want it back
I'm starting to see everything you lack
Boy, you blew it, you put me through it
I wanna uh-uh-uh-uh-uh-undo it

[Outro]
You stole my happy, you made me cry (Na, na, na, na, na)
Took the lonely and took me for a ride (Na, na, na, na, na)
Boy, you blew it, you put me through it (Na, na, na, na, na na)
I wanna uh-uh-uh-uh-uh-undo it