The cyber-hate came flooding in after TMZ posted the pics of Aldean -- a huge country singer who happens to be MARRIED -- putting the moves on Kerr at a crowded bar on the Sunset Strip.
Sources connected to Kerr tell us ... she had NO IDEA Aldean was married ... and if she would have known, she would have shut the whole thing down from the start.
Even though Kerr didn't go home with Aldean, people attacked her online ... writing terrible things on her Facebook page including:
"Disgusting homewrecking tramp!"
"what is wrong with you taking advantage of a married man while he was drinking."
"everyone thinks ur a slut!"
For the record, people have ripped Aldean on his Facebook page too. He has since apologized, chalking the whole thing up to a bad drunken decision.
We reached out to Kerr -- so far, no comment.