I think this was one of the best episodes in the series. The storyline was very believable and I though the way Greg had to face his own life in dealing with Maggie is a great reflection of how life works. Life isn't compartmentalized; our careers, families, marriages, hobbies, faiths and so forth all impact each other. We are one person, not a collection of fragmented parts.
Jules calling Greg on his lack of compassion at one point no doubt had an impact on him and likely helped him to be able to peacefully diffuse the conflict. It also reminded of Sam of one of the things he really loves about her, which was also nice to see.
These are the kinds of episodes that take a while to digest because they make us think, and that is a good thing.