Disgust is my lack of approval.
When I strongly disapprove, I am disgusted by what I am disapproving of.
The need for approval can be either subjective or objective; never adjective.
I cannot be disgust.
I can be objectively disgusted by others bad behaviour.
I can be subjectively disgusted by my own bad behaviour.
I subjectively disapprove of myself and I objectively disapprove of others.
Disgusting behaviour is my judgment of myself or other people.
It is behaviour that strongly conflicts with my standards or my boundaries because I believe it to be morally, ethically or socially wrong.
Disgust is a principle.
I react to disgustingly bad behaviour on the principle of not tolerating bad manners.
With no need for approval, I have no need to approve, no need to disapprove and no need to be disgusted by the behaviour or manners of myself or other people.