Not surprisingly it says (regarding marital separations):
A surprise decision feels disrespectful and painful. This is why the hardest hit are those who didn't suspect a serious problem. They are unprepared, they are stunned, their world is in a tailspin.
No kidding. She goes on to talk about the "review work" that one had to do when trying to make sense of how the marriage fell apart. She writes:
Your preoccupation with the relationship, who was responsible for what, and what this means to you now, is natural and healthy review work. But it is work, like the grief after the death of a loved one.... The sense of failure and disappointment can be crushing. It obscures the job of gradually separating your marriage from your parenthood....Usually, review work permeates much of the first six months before (at least for the person who is considering the separation) and after the separation. If the separation was unexpected, the review work is pervasive for at least a year, sometimes more. The easiest (and most peaceful) response to review work has been described by a few people as simply coming to no definite conclusions. Not all questions have answers and not all "the whys" are worth pursuing. Asking, "What's going on here?" is more helpful than "Why?" Release and peace do not necessarily depend on taking a course of action on a position; simply acknowledging the experience can be enough.