Maybe see if there is someone you can connect with in your local foster caring community. Most foster parents are long term and take many children temporarily through the years. Perhaps you could give your house to a younger fostering couple that rents currently, or put it into a trust to be used as a group home?

If you are near a hospital or cancer center, you could leave the house to be used as a place for families to stay near sick or dying loved ones.

Either way, its a beautiful thought you have, I hope you find a way to make it happen. <3