If you don’t take the money, she’ll probably think that her money isn’t good enough for you which will make her think you think there’s something wrong with her. If you take care of your own but she just happens to be worth a hell of a lot more money than you, she’s not gonna think less of you and she’ll never ask for that money back. If you get greedy or if you become a free-loader, that’s a different story. Just take the money.
edit I had a bit of a sugar-mama a few years back when I lived in NC. The only time she got on my case is when I lost my job and didn’t put any effort into finding another one. Take the money.