You don't know what the phrase means. An ad hominem attack is not an insult, it's using something unrelated about the person to claim that their argument is invalid. Saying "Bob is gay, thus he's wrong about if marijuana cures cancer" would be an ad hominem.

I simply insulted him (You? The context feature doesn't show what I replied to.) for using the tired liberal bullshit of "That's not real socialism" every time socialism fails.