Joss Whedon once said that if he wanted to make the audience cry, he'd have Alyson Hannigan cry. In Hannelore, Jeph has a similar means of breaking hearts.
I don't think Faye's being actively mean here, it's more about Hanners being averse to change, and more than a bit naive (which is true to her character). Hanners getting this upset is unfortunate, and perhaps Faye could've put it more gently, but she's understandably not feeling too good herself and as TRVA said, it's a difficult lesson than Hanners needs to learn. Things can't get resolved with a fingersnap, or by asking really nicely.
That said...if we're going to ease up on Faye for being imperfect and human, that same courtesy should extend to Dora. Both are divisive characters and understandably disliked by groups within the fanbase (with some overlap from fans who dislike both characters), but it feels like the goalposts are constantly being moved with Dora, in an effort to blame her for what's happened to Faye, or criticise her handling of the situation.