Also I should add that she knows about Mr. Money Mustache. I don't believe she's been to the site much but one of her best friends and roommates is the one that introduced me to it.
I'm kinda hoping that she asks me about my investments, several friends have asked for my advice and opened accounts at Vanguard based on my advice and I've kinda found it best to mention to a few people that I'm paying very low fees. One friend was talking to me about it and recognized that I have Admiral shares and he told it to a few friends that were looking for advice in starting to invest and so that was great as I was able to get them on solid footing (one of them opted for active funds against my advice, but it's her money).
I'll admit that I have mentioned to people that I plan to retire before 40, mostly to get people to ask me how because it isn't difficult what I, and many here, are trying to do: make money, spend less than I earn, and invest the different in low-cost index funds.
I'm hoping that I could slowly hint at Vanguard until she bites.