There is a book called The Hard Questions that discusses various questions you should ask yourself and your partner before you get married. I found it very useful. Although your sister is not in that situation, perhaps if she really looked at these questions (what do you both really want, etc...), she would come to her own conclusions. She certainly could see other people, since this person is not around much, and the fact that you mention his money over say, his interest in teaching one of her children to play softball or something, is fairly alarming. One ought not to get involved in a relationship where the power is so extraordinarily unbalanced. He's already possibly seeing other people (that's what it sounds like), and she needs to get much more power of her own, be it moving into a more affordable place or a better job, or familial support with her children to free her up to get better skills. Marriage to a person who has shown no real interest in supporting her family is not the answer. It's hard to meet a good partner, but you only really need one, so if it takes a few years, it's worth it. And she already has children, so presumably her biological clock isn't ticking, like some other people. She's way ahead on that score, in a lot of ways. I think the question here is how can she become a powerful person in her own right? Completely aside from a marriage? That problem would be there whether she was married or not. It would be wonderful if she could outgrow this man, as he is holding all of the power now and that will continue to get worse. Her children will suffer if she continues to look elsewhere for financial support, as she is already sounding like she's waiting around for someone else to make the decisions in her life. If not this man, the next one. Since money is power, I would suggest that her first move would be to consult a financial planner and a career guide, and build her life into one that mirrors the strengths this man already possesses. Like someone already said, 'it's only been twelve dates.'