Attached : The New Science of Adult Attachment and How It Can Help You Find--And Keep--Love by Amir Levine and Rachel Heller (2012, Uk-B Format Paperback)
If I had read this book when I was 18 I would have had so much less drama and emotional pain. The opening story described my past relationship perfectly, it was crazy and reassuring to read all the similar stories. Definitely has changed the way I think for the better.
Informative, easy to read. Couldn't put it down. Every adult should read this to htlp understand attachment styles & behaviour to improve relationships & happiness.