Context dear boy...context. You leave your children alone to socialise and as a result one is allegedly abducted and you are complaining about the effect it has had on your sex life. Can’t you see how self indulgent that might appear ?
You use words like "whinge" and "complain" but I don't think that is what Kate is doing. She is IMO writing a truthful, heartfelt account of how the disappearance impacted on her and her family's life. Any autobiographical book is self-indulgent, it assumes people want to read about you and what you experience, think and feel. If you don't like such books don't read 'em. And before you start, it was called "Madeleine", not because it was a book all about the first nearly 4 years of a little girl's life, but because it was a tribute to her, to the fund in her name, and because it was her disappearance that set the whole thing off in the first place and her name was internationally known. A book solely about Madeleine would have not been of interest to most people IMO.