Lydia Hoffman owns the shop on Blossom Street. In the year since it opened, A Good Yarn has thrived&mdash;and so has Lydia. A lot of that is due to Brad Goetz. But when Brad's ex-wife reappears, Lydia is suddenly afraid to trust her newfound happiness.<P>Three women join Lydia's newest class. Elise Beaumont, retired and bitterly divorced, learns that her onetime husband is reentering her life. Bethanne Hamlin is facing the fallout from a much more recent divorce. And Courtney Pulanski is a depressed and overweight teenager, whose grandmother's idea of helping her is to drag her to seniors' swim sessions&mdash;and to the knitting class at A Good Yarn.