she's blinded by love

I don't understand her, the girl he was with, the girl he loved while he was mine I don't understand a lot about her, but, I wonder how do you do it? didn't you hesitate? surely it crossed your mind, if this is what he does- going behind his girls back, choosing someone else as he whispers his love in your ear, surely to God, she stopped, at least for a second, to wonder, will he do that to me? she's my enemy, she's the girl who helped him destroy me, but I honestly wish I could warn her, he will do everything to her too.