I need help finding a place for my 85 year old mother to stay. Advice?

It sounds to me like you don't need to find a place for your mother to live if she's still doing for herself. Maybe look into hiring a caregiver for what is called 'sleep-duty'. That means they stay overnight at a client's home who is pretty much independent and don't really have to do much of anything for them. A sleep-duty caregiver gets up a few times during the overnight and checks on the client to make sure they're in bed and not up wandering around. This sounds like something that might work for you.

Consult a Senior or Center for Aging organization to help you through these life decisions.

With only SSI she will not be able to afford any LTC facility on her own, and will need to make applications for medicaid. This will mean nursing home, and certainly not one that is at all luxurious. I would contact some of those agencies that will help you and Mom explore options; such as "A Place for Mom". These places will assess income, and probability of finding placement. Often Board and Care homes are best for those such as Mom. The agency will drive you both to suggested facilities when Covid time is over, or give you online access to interview now, and take virtual tours. They are payed by places that you choose if you do choose one. Placement will be more difficult with only SSI but it has been done and I hope some will chime in who found it doable.