I'll qualify my opinion by saying that if other people, or indeed you, have found this book helpful - then that is great.
However, I resent the assumption that as "wives of" we are somehow in more need of self-help or suchlike. I truly loathe it when people ask me "How do you cope?" or tell me how much they'd hate to have my life and then look sceptical when I tell them that I cope very well and that my life is quite happy. I neither expect nor ask for pity.