It doesn't resolve all the issues, like health care decisions for instance, but I opened a joint bank account with my Dad so at least I could talk to the bank and, when the need arose, get money for him and pay his bills. With my Mum we have her property in trust which resolves a few other problems. Power of attorney is the best legal option I believe but if she is not ready yet I am not sure what you can do.

Good luck whatever it is.