That was the aspect we knew, but over the show has gone on, we have learned more about the characters.
Her motive was clear, ruin the team to get back at her husband. Sometimes people do good and bad things. Winchester from MASH had a similar Christmas story if I recall.
Higgins is a great guy, except last season he was the tool Rebecca used to do most of her dirty work. Not to mention he covered for Rupert for years. You didn't have an issue with him hosting a Christmas party for the team without family?
Keely was clearly just a superficial model/WAG, except she has a very soft side and great person, especially with Roy.
Jamie was and is still superficial. He has moments where he cracks through.
Ted was the best guy in the world last year. This season, it seems clear(to me) he's jealous of the Dr. and while he's nice to her, hasn't given her credit, is wary of he nad hasn't referred anyone to her. They set it up last week to send the Captain, but Ted handled it his way.