You are in my thoughts and prayers that this will not end up being an extra burden on you for very long. How is the housing market where you are? Is there a chance that they can find a house nearby to relocate into? Then set them up with some in-home help?
It would be too much for anyone to let them stay indefinitely without some plan such as that... Or perhaps get them an apartment in an assisted-living facility... My mother lives in one and it is great! Here is their link to give you an idea:
She has her own little apartment with a kitchen and has lived there for nearly five years. She has a cleaning person come in weekly and is provided two meals a day included in the rent. The rent isn't that much higher than a little house or apartment would be.
I hope this helps a bit. Remember to take deep breaths during this time and keep a sense of humor. You are an angel Barb...
Love and Hugs from Glenda