Chris Brown performs She Ain't You on The Today Show's Concert Series 2011 (HQ video) 

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Lyrics:
you make it hard for me to see somebody else
i'm calling her your name yes mixed up, cause i'm thinking about you
... for babe, i never wanted us to break up, no not this way
but you don't understand it girl
she touches me, i'm wishing that they were your hands
and when i'm with her it's only about the sex
with you i had a bad romance, and if i could just trade her in i would
cause nobody can pass you up no
yeah, i think i better let her go, can't leave you alone
baby ...i'm with her, all i want is you
i wanna leave but i'm afraid, that you don't even feel the same
now i realize, that she ain't you, she ain't you
oh no no no no, oh no no no
na na na na na
she ain't you, oh no no no
cause she ain't no she ain't
i've been sleeping out, the ... are nice now
it's not the same in my bed
but if she found out what's going on in my head
it will be all bad, have me right back, but she don't understand it girl
she touches me, i'm wishing that they were your hands
and when i'm with her it's only about the sex
with you i had a bad romance, and if i could just trade her in i would
cause nobody can pass you up no
yeah, i think i better let her go, can't leave you alone
baby ...i'm with her, all i want is you
i wanna leave but i'm afraid, that you don't even feel the same
now i realize, that she ain't you, she ain't you
oh no no no no, oh no no no
na na na na na
she ain't you, oh no no no
cause she ain't no she ain't
i think i better let her go, can't leave you alone
baby ...i'm with her, all i want is you
i wanna leave but i'm afraid, that you don't even feel the same
now i realize, that she ain't you, she ain't you
oh no no no no, oh no no no
she ain't you, oh no no no
na na na na na
cause she ain't no she ain't you.