All marriages are/were to varying extents. I would go so far as to say that being able to "pencil out as a sensible business transaction" is a key element of most/all longstanding marriages.
Being the 40yo guy marrying the 20yo girl is like being the 40yo guy daily driving a Ferrari. Sure there are some pretty big downsides in the practicality department but you're rich enough to paper that over (this sentence is specifically crafted to apply to both parties).
Being the 40yo guy marrying the 20yo girl is like being the 40yo guy daily driving a Ferrari. Sure there are some pretty big downsides in the practicality department but you're rich enough to paper that over (this sentence is specifically crafted to apply to both parties).