How do you do it?

How do you do it?
Fear in my eyes, my body trembling,
You raise your voice,
Your hand,
How can you do it?
Say words so hurtful, 
“I wish id cheated” echos through my mind,
“You’re nothing”
As if you haven't hurt me enough,
Numbness spreads as i shake,
My mind echoing your words over and over,
How could you do it?
Look me in the eyes with nothing but anger in yours,
My tears caress my face in place of your hand,
My sobs comforting me as you should,
Yet you remain unfazed,
How do you do it?
Walk in a room and act like i don't exist,
Breeze past me like a stranger in the street,
As if 4 years means nothing,
My body numb as i drag myself through the days,
Wondering if i deserve more,
How could you do this?