Men in Midlife Crisis by Jim Conway available at Amazon
I think it was Was2 that recommended this book to me way back when I first came here. It was a great book. In fact I gave my copy to my H, and after he read some of it, he even admitted that he was going through MLC. Didn't do him any good, it just meant that he had an excuse for his bad behavior. But I think it would be a good book for an outsider trying to understand what the MLCer is going through.