Why i did it

You were nice to me,
But I didn't bother,
We did have a great time
But I didn't bother,
You showed me a whole new world
Where I didn't know exist
But did I.
I did not,
You kept your promise,
You sure did,
But I was selfish
Four years of togetherness
Didn't bother.
How did I change so much
That I couldn't even recognize me
But you did,
You always did.
We did argue, had fights
did we care,
No you did not.
You did your part so well
That I cheated on you
And still I don't know
Why I did it.