While we're on statistics both you and you spouse should own long term care insurance. There is over a 70% chance one or both of you would benefit from it.
Still want to pick and choose when you like to use odds.
It can't be that high. The average premium for long term care is 2500 a year at 55 and 4000 at 60.
Assuming you carry it from 55 until the price gets too high which is probably around 70-75. Assuming the average cost over that time is 5000 dollars then over 15 years you would have paid in 75,000.
However, the average payout is 150,000.
This means with profit and overhead there is probably closer to a 25% chance of using it when covered.
It is almost certainly in someone's best interest to invest that money rather than use it towards long term care insurance. Why pay 75,000 dollars for something that is only a 25% chance of paying out 150,000.