The situation with my MIL is getting pretty dire. DSIL & her husband live with MIL. MIL presents as being quite rational, but according to SIL, she is urinating in wastebaskets, not attending to personal hygiene, and seems a bit phobic about the bathroom in general. MIL has started bouncing checks and when SIL wanted to help her balance her checkbook, MIL refused and hid checkbook saying everything was fine. MIL drinks a large bottle of wine daily and smoke 3 cartons of cigarettes a week. She uses a cane and walker since breaking her hip last July, and did not cooperate with PT so probably won't progress with her ambulation. She smokes in bed, and BIL recently pulled her away from the stove when she was leaning her face into a lit gas burner to light a cigarette (looked like her hair was going to catch fire). BIL says she doesn't wash her hands so they are concerned about food safety with shared things such as a loaf of bread.
SIL and BIL are on a steady diet of whiskey and cigarettes. SIL is unemployed and has some health issues. She is not terribly nurturing (nor is MIL), but I would say she is trying to do right by her mother to the best of her ability, but she isn't cut out to be a caretaker.
MIL is belligerent, mistrustful and uncooperative, and wants to be just left alone to do her own thing in her own home. SIL & BIL are talking about just moving out.
MIL cannot safely live alone, but is a hazard for anyone living with her due to smoke and fire risk. How and at what point can she be made to accept different living arrangements against her will? Would withholding (or at least decreasing) wine and cigarettes be an act of cruelty or the responsible thing to do?
Brothers are all angry that SIL isn't doing a better job managing the situation, but nobody is really jumping in to help. There is a bad dynamic because MIL said SIL will get the house when she dies. SIL and BIL are paying very little towards living expenses, so brothers think they are taking advantage. SIL says she doesn't even care about getting the house at this point, she just wants out of this servitude.
I am going to ask SIL what I can do to lend support. I do get along well with all partied involved. Any advice?