I was wondering: Now Don's life is going downhill, why doesn't he go back to Suzanne? I don't remember one of them really closing that door and would it be too much out of character?

Not that i would like that to happen: I think Suzanne is a bit of a strange character: in the beginning she was extremely tongue-in-cheek kind of girl and pretented to be very independent but the moment she started sleeping with DD she suddenly turned out to be (or pretend to be) a sort of generous, caring, and very clingy person.

I agree, Minous.  Her character did a complete 180.  Remember when she was out jogging early in the morning and DD was driving along next to her, trying to get her to come for coffee?  She seemed so sophisticated, steadfast, and very savvy as to why the liaison would be bad bad bad for her.  ANd of course 100% right.  Quite a contrast to her later submissive behavior.  The image of her skulking away with her suitcase, tail between her legs as it were, makes me shake my head.  GO TO THE DOOR, I kept thinking.