She is 91 years old. Her only son (my husband) died in Dec. 2013. She can't see and can't walk well at all. Needs someone with her to go to bathroom. I'm feeling guilty about the amount she spends on care and the fact that she's lonely even though she has someone there with her 24 hours a day. My house has steep stairs, and I'm afraid she'll become disoriented at night and fall down the stairs. There's only 1 bedroom upstairs on the main floor, and I would have to sleep downstairs. I really don't want to bring her here (8-hour drive) to stay with me, but I feel guilty. I also cannot make frequent trips to see her because of the distance we live from one another.
First, I think I might shop for a less expensive care-giver. Although, when she runs out of money (IF she runs out), it doesn't make any difference WHAT she paid, as she'll go on Medicaid. But. Have you discussed with the agency the possibility of her 24/7 care giver taking her to lunch? Just taking her for a ride? Do you have an Adult Daycare Center near her home that could take her a day a week so she could interact with other seniors? One near my home that we use for mom charges $63 a day, very little in the scheme of what she's paying.
What I might try is taking her to visit the facility you've identified. The staff will roll out the red carpet for her . . . take her back to your house for dinner and have the kids/grandkids over. Keep her overnight a night or two, and see if you can get her agreeable to TRY it. Emphasize that, if she stays a month and really doesn't like it? She can go back home.
If you go through all that? You've done everything you can do unless you want to have her admitted against her will. Doesn't sound like you want to do that.
It makes the decision about you, not the person who needs help.
DO make decisions based on safety, quality of life, level of care, planning for advancing needs, convenience, & comfort for the MIL.
But don't rush. If MIL is not in a crisis now, there's no reason to rush into hasty changes.
Take care of yourself. Work on you and adjusting to your new normal. Doing anything else is terribly unfair to yourself.
I would think your mother-in-law's best interest would be to find a really nice continuing care facility that is closer to you. That way she would be surrounded by a lot of different people.... and at the facility, the employees work 2 or 3 separate shifts, thus they are able to go home and rest, and be fresh for the next day's work. That way you could go visit and have great quality time, you could even arrange to have dinner with her once or twice a week so you aren't dining alone.
If she came to live with you, and with her very limited eyesight, it would take her quite awhile to learn her way around your house. And yes, steep stairs and elders can be a dangerous combination. You also would be doing the work of 2 or 3 Caregivers, unless you hired one or two people to come in to help. Then you are back to square one, again.