Disappointment is anger with the bitterness squeezed out.

They say it's in the eyes, but I'm reading your whole expression
and it's written clearly - I'm a little less than sick of you.
Your disgust is muted; fingernails against my flesh - not knives.

But somehow this hurts worse.

There's a dull pressure squeezing itself round my body
and that lump in the throat is back to stay.

I'll cough up bloody globules
and prove my worth.