Feeling depressed?

For those considering buying this book on a lark. My friend purchased this book having had no prior evidence of depressive tendencies. She thought the book provided a good giggle and bored her friends (including myself) silly by enlessly quoting extracts from it. However around the time she read it, or shortly thereafter, began having suicidal thoughts and often expressed negative sentiments such as "it's all downhill from here" and "Shopping is merely a short term cure for our woes" She used to enjoy tennis and travelling, now she can hardly summon up the energy to check her mail. She sent her pet goldfish to her aunt in Madagascar and started watching daytime TV.