She bought them yesterday after returning from the work trip. It was recommended by her best friend (who was cheated on, I believe, or it came very close, now divorced) -- I will ask her what she thinks of it, I'm pretty confident there's no significance that she would choose this one over others, it was a recommendation by a person she trusts (one who both warned her that an attraction to this man was not a dangerous thing but also told her NOT to talk to me about it ... all of which is to say, not the greatest advice giver.) My wife is feeling her way through this -- still coming to terms with the reasons she has done this, but I believe she is taking steps, not throwing up more walls.
As for the book she bought for me, I know her, it was a self-punishing gesture. She is apologetic and has repeatedly assured me that she wants me to be happy. I believe it was her way of saying "maybe there's something in here that tell you if you could be." A weird apology if you will.
All of which is to say, I do not share your alarm in this regard. I may yet be proven wrong, but I think the motivations here are positive.
I know it's hard to convey these details via a forum post, but I do honestly trust her when she says she broke it off with him (starting that night in which she texted him, while I was standing there, that it was over and to not contact her again) and that she recognizes the stupidity and selfishness of her actions (her words).
That's potentially naive, but knowing the alarm bells that were going off in my head previously, there are none ringing now, I see genuine actions here. It does appear that the fog has lifted.
That said, the risk of relapse is a question for another day.