Cats, I've thought this through a bit more, and decided that the optimum city is one with a small but significant proportion of emotionally unregulated people. You want enough people that the book is stocked by the store, but not so many that the book is sold out!

If you don't live in such a city, you must of course move before going to the bookstore, which could delay things quite a bit...
I think it would be fab to have the book to show T. It would show that you are taking on board what she's saying and you are willing to work with her. And perhaps it will make her more amenable to tackling one important thing at a time rather than expecting change in every area overnight