I found this book to fit quite well with what I have learned about invalidation and invalidators, and could readily identify with the techniques that invalidators use. I found that it was a book to take lightly however, in that only a small proportion of the counter-tactics, or ways of managing your own feelings, were actually useful - being of the general self help, common sense or easily found on the internet variety. I also found the writer's tone unhelpful in places, as he writes as someone who is clearly a victim of such behaviour, but still rather angry about it (though may be unwilling to admit as such). As a result, in places he could be accused of the very thing the book is about, sometimes writing in a style that is at best impatient - at worst insulting - whilst simultaneously telling the reader that they would somehow be ridiculous to be negatively affected by what he has said. You can move past it and just extract the helpful bits, but for me it detracted from the feel of supportiveness that is otherwise present by his appearing hypocritical. Fans of the 'tough love' approach to therapy or self-help may find this refreshing however.