"Sheer Abandon" by Penny Vincenzi

Penny Vincenzi is a British treasure - beloved in England for years, and just recently discovered by Americans. 

Her novels are usually historical - anything from WW I (No Angel) to her latest in paperback, Sheer Abandon, whose story has its beginning in 1985 when three young women meet while traveling in Thailand and become friends. Fifteen years later, the three have lost touch, but are brought together again by a young woman's search for her birth mother....one of the three abandoned her newborn at the airport as she arrived home from Thailand. 

Vincenzi's fiction is the perfect summer read - full of engaging female characters, plots with just enough depth to be fascinating, and usually a surprise or two.