From what little I know of acting, I think you need to cultivate a thick skin and a hard shell to have any degree of success. I'm sure that Megan can be tough, I'm sure that she would have needed to be. But firstly, that doesn't mean that that's her defining feature, and secondly, I wonder if people would be half as 'shocked' if she was a man...?
As for the blind gossip thing about the PA - well, allowing for exaggeration, I'd have been utterly furious if someone who was meant to be taking care of the small stuff let me wander off a plane in front of the international media with the tag hanging off my dress too! Not to mention the knickers on show skirt - I'd be mortified. Especially since media interest is so high at the moment and there have been such nasty stories and all that crap with her family.
I'm not an unthinking Megan fan, but I like to be fair and I think she's being judged harshly, especially in the press.