Glynnis MacNicol wisely says about writing that "not telling the truth leads to bad writing." She's spot on about that and quite a few other things in her new book, "No One Tells You This," which she discusses with Don on this week's episode. The two talk about her 40th birthday, solo travel, and how Glynnis once ended up eating steak for breakfast. Her book is a memoir about being 40, single, and childless, and although her stomach turns slightly at the phrase "deeply personal," Glynnis has received lots of praise for her book's honesty and clarity, which comes across in this week's episode.