Everyone's situation is vastly different so do what you feel is right for your individual circumstances, there is no right answer.

These points, although "funny money" currency, do have a dollar equivalent, although take it with a grain of salt. For instance, I used 25,000 points at the SF JW when the nightly cash rate was over $500 but I would never dream of asking for $250 because I would never pay $500 out of my own pocket for a night anywhere in the world.

A lot also depends on your cache of points, your financial situation in life, your age, the closeness of the relationship and real likelihood you'll have the time & inclination to use them in the near future before they devalue furthur.

In fact, the last 5 personal extended trips I took in the last 18 months (2 different friends, 2 different newer romantic interests, 1 kid plus her friend), I was fortunate to use points for us both on the air, hotel and rental car and didn't ask or expect a dime in return. And I probably bought the concert tickets too since these folks aren't well off. But that is me and my current circumstances. And of course they reciprocated in some manner although nowhere near the "retail" value.

Had I been less well off, had more time to personal travel on a more frequent basis, been half my age, had less points, had other trips and uses for the points in the near future, maybe I would be less generous. You earned the points through whatever hard means, e.g. business travel, credit card use, monitoring of this boards and all the hoops and gotchas of actually using the points - a real time suck, btw. Asking for some sort of reimbursement is not out of the question if you can't justify gifting outright, just do it upfront with clear understanding.

Maybe 1/2 of 1/2 of the retail price for 3 nights is fair? Only you can judge...