I was going to tell you that what you are doing is what families do...until you said she was in her early 50’s!!!!
That means you and your wife are in your early 30’s or less.
She could live for another 30 years, or more, in relatively good health...you have to consider that. Everything in your life will be affected...sex, money, privacy...you have kids? Early 50’s is far too young for you, or she, to be considering a move like this.
I doubt it would serve her or you well to have her move in.
My best suggestion...call Dr. Laura, get beaten up and take her advise.
I agree with norge. I think it might be best if you found her some low income housing near you instead of moving her in with you since she is only 50ish.
Does she have some serious illness and is that why you have decided to have her live with you?