I have done a quick check of a couple of dictionaries, and it appears that "repulsive", "repugnant", "revolting" and "repellent" (inter alia) are all reciprocally listed as synonyms for each of the other words. My own sense is that the difference, most particularly as between "repulsive" and "repugnant", turns on whether the object of (revulsion/repugnance/etc) is perceived as personal or extrapersonal. By that I mean, for example, if a person hates olives, the prospect or thought of that person himself/herself eating olives is "repugnant" to that person. However, the sight or account of someone else eating olives is "repulsive". Am I forcing a difference here, or does anyone else have the same sense?
I think you are onto something here. I suppose the nuance might stem from one's inability to separate physically from oneself.
"Others find my behavior repulsive" sounds just fine.
"I find his behavior repulsive," likewise.
"I find my behavior repulsive" has a bit of semantic dissonance about it. It sounds unlikely, but not impossible. "I find my behavior repugnant" does not have that same feel of xenonymy.