My wife and I talk about this occasionally as well.
She was concerned that indefinite, full-time cruising meant indefinite discomfort and the possibility of being homeless and jobless if something went wrong (read: boat sinks). She's quite a bit of a minimalist and doesn't mind not having much stuff (regularly donates/discards lots of our stuff anyway).
I originally was pushing for a long-term (multiple years) liveaboard vessel in the 45-foot range, but she didn't like the financial picture that painted. We could spend similar money on an apartment and have a real investment. Her ideal picture, instead, was a smaller, more affordable boat that she's be comfortable on for many months in a row, maybe a year, but keeping our land lives to come back to.
In the end she managed to convince me that a smaller (~35 foot) cruising boat is what we should upgrade our current 27-foot boat to, and a year or so of cruising is what we should plan for.
See what I did there?
But in all seriousness, you need to find out what her ideal cruising would be like and see if maybe it would be good enough for you. If it's her dream, her idea, her boat, she will get behind it and and make it happen without you "getting her" to do anything.
s/v Laelia - 1978 Pearson 365 ketch
s/v Essorant - 1972 Catalina 27