Do you feel that this philosophy really works or is it a way for a person to empower themselves and feel better about what is happening to them
My take reading DBg was that it's more about interpersonal dynamics in a relationship and how to affect them. If you mean does DBing bring a spouse back from an affair, then I think there's a bigger can of worms having more circumstances and issues. Certainly DBing may still affect the WASs' relationship with the LBS for the positive. Certainly, the idea of looking at the LBSs' contribution to the failure of the relationship is important, without elimination of those behaviors/patterns and consistent demonstration that they have been purged, one can't expect a WAS to wish to come waltzing back into the same old relationship they wanted to leave. And what certainly doesn't work are many of the LBSs' natural tendencies of behavior when a WAS does leave or have an affair.
It is empowering because instead of feeling hopeless, DB gives the LBS a plan, and having a plan gives one a sense of control, which helps eradicate the sense of hopelessness. Very importantly, the book points out the need to go on with one's life and to focus on one's own interest, and that's very powerful because it accomplishes several things: By GAL, the significance of the WAS is diminished instead of being the object of obsession. It gets the LBS on track with their life. The new life the LBS builds also feeds the LBSs sense of self-worth and self-esteem which has typically been shattered by the event. The LBS typically shows dependance upon the WAS's valuation of the LBS. That new build of self-love makes the LBS more confidant and centered, which is an essential place to be whether you're in a relationship or not, and chances are, the LBS had lost themselves along the way during their relationship, and you can see that by the degree that LBSs despair when their WASs leave, so that type of help is essential.
You called it a "philosophy" and that reminded me to consider, not a philosopher, but an ancient poet, Ovid. He wrote on the subject of abandonment, writing:
"And if you're grieving deeply, look happy, lest she see it, and laugh, when tears come to you. Not that I order you to break off in mid-sorrow: my commands aren't as cruel as that Pretend to what is not, and that the passion's over, so you'll become, in truth, what you are studying to be".
In effect, Ovid's saying "act as if, don't show your feelings in front of the WAS, practice detachment, and fake it till you make it". This wisdom has been around for eons.