spitting image of a prince charming psychopath - Psychological thriller

Apart from the "Ten Little Niggers" Agatha Christie (studying in 5th class) is the 1st time I plunge into a thriller!
I'm pretty well fallen since the latter is, according to the reviews I've seen, the book of Mary Higgins Clark as "psychological", giving a large part to the personality of the psychopath character. It is also stated at the beginning of the book that the author has obtained the opinion of psychiatrists to paint a portrait as realistic as possible even if the character of Erich proves particularly twisted!
However at the beginning of the novel it's just someone a little obsessive, possessive and perfectionist (but have we not everyone our little faults!) And these seem, at least initially, be minimal compared to protection in warm appearance it offers to Jenny and her two girls.
As a young married we see that from the start it the "reframes" not enough, veiling the face and pretending to ignore his foibles and say that he suffered and that it will pass with time. But the mask gradually falls and the psychopath not only reveals its true nature but happens to make Jenny isolates more and more, lose confidence and develops a sense of guilt.
The theme of missing children and blackmail that we can do about them seems to be a favorite subject for Mary Higgins Clark. In fact, despite being a woman of apparently free choices, Jenny finds herself caught in her marriage trap and must face her Prince Charming turns out to be his persecutor to the extreme limit.