You wife is right (the secret to maintaining a positive DHQ (Domestic Harmony Quotient) is just accepting that as a basic premise of home life).
Basically you want to set a perceived value for the work which will allow some other person to make a living at it — anything else devalues the work and makes that impossible.
That said, a work-around is to set the price high, but then say, “you’re getting the buddy discount”.