KElly fans can be harsh, they bashed clay pretty good, xtina, hilary duff, lindsay lohan, Avril Lavigne, all of whom Kelly is actually friendly with (she even did a concert in Texas with Hilary Duff..Avril wrote Breakaway, Xtina wrote Miss Independent, Kelly toured with Clay, etc...).
Part of it i also, Kelly fans for awhile had diect contact with Kelly, Kelly used to post on her own sites along with her close personal friends. That stopped litterally over night, but a good number of the fans still try to hold on to that connection and go overboard with it, and some really young fans simply don't know any better yet, to them, defending their favorite artist, no matter how they do it is the right thing to do, and we can't knock them for that, but we can explain to them what is wrong with some of the methods so they will understand better (unlike some sites that simply bash them, ban them, give them a hard time over it, and make it worse, when the kids really don't mean any harm and are trying to do the right thing).
As for Kelly.. it's not a secret there are people at RCA and 19 she doesn't like, yet, she never talks bad about anyone, that alone should be an example for her fans to follow, and we've all heard other artists bash others in interivews and such.. never once do you hear Kelly do something like that. The tabloids hate her for that, they have nothing bad to write articles about...lol.. they tried with Kelly vs. Hilary, but Kelly simply sent Hilary a pair of boxing gloves and a note with 'let's get it on!'.. shot the tabloids right down...lol
I think people also forget the whole time Kelly and David were together, Kelly was still pregnant with Justin's baby from 4 years ago (remember the hay at their wedding? hahahaha)