That episode was sensational, my god. Heather getting so cornered that her mean girl came out with Angie K basically telling her to sit and eat her food at dinner, it's fascinating how every one of these women can tap into a bottomless well of darkness.
Lisa is the only main cast member actually showing some demonstrable growth from last season. Her refusing to back down with Jen was great to see after how she used to get steamrolled in the past. Whitney is also having a great season even if her tactics are blatant, there is no ally she won't betray even her own family and the show is all the better for it.
I'm convinced Angie K only had her snowflake withheld because the third season is traditionally when these women see a salary increase and they're just waiting until next season when Jen's portion is freed up to promote her (and hopefully Danna). She knows how to play the game perfectly by getting involved in the conflict just to trigger an apology from Jen and get Lisa further worked up.