A little background - I'm 25 M, 3 years into my journey towards FIRE, and at a decent pace as of now. For the last six months, I've been seeing someone who I believe is going to be my wife someday. She's 23 and going through grad school, so should I marry her, all her debts will become mine. She seems frugal enough (cooks at home more often than not, bought a used car for next to nothing, etc.) but at this point her financial frugality might be more out of necessity than out of a desire to save. I think she's smart with her money, but only compared to the masses. She still likes to go out to nice places to eat, go see movies at overpriced theaters, enjoy nightlife, and so on. I believe that she envisions her future as being a fairly plush lifestyle (10-15% savings rate), where as I would like to continue on the path towards FI (50% or more savings rate).
Question: How to I introduce mustachianism to her without freaking her out? How I do go about explaining to her the benefits that can come from all the positives of mustachianism? What are your favorite "arguing points" that I could bring up? Any advise would be greatly appreciated!