sad, in its purest form

It seems like every time I start to forget you, I remember you all over again.
I keep seeing your face, the look you gave me the last time I saw you.
I was shivering, you held my eyes with yours, and I thought I saw something.
Guilt. Remorse. Lust.
I saw "I'm sorry" and "You got what you deserved" all in the same glance.
I know my eyes looked hard.
Masking my emotions is what I'm good at.
Behind that, though, I was simply sad.
Nothing else.
Just a small, simple emotion.
The opposite of happy.
A word we learn before we even attend school.
Sad.
Just sad.
In its purest form; sad.