Similar meaning, but more formal:
* Offended
* Disparaged
* Humiliated
* Slighted
* Disrespected
Similar meaning, but more informal:
* Put down
* Slammed
* Roasted
* Dissed
* Put in their place
More specific words:
* Scorned: If the insult involved being treated with contempt.
* Mocked: If the insult involved being ridiculed.
* Defamed: If the insult damaged someone's reputation.
* Vilified: If the insult involved being severely criticized or condemned.
The best word to use will depend on the context of the situation and the specific nature of the insult.