Looking at her past, and talking to friends, she is deathly afraid to be alone. And it looks like she's always lined up her next man before leaving the last. It's my guess that this is the same behavior.
Part (or maybe most) of that could be a security issue with her. With you, it was financial security she wanted. Maybe it is with the other men, too, or maybe it is to feel secure about her looks, sex appeal, etc.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!
