I think she believes if I'm her guardian, I'm responsible for her. My dad has been dead 10 years and she keeps saying she's never lived alone. When I remind her how long it's been since his passing, she reminds me of how she doesn't like living alone. We've never been close, I'm still raising a family and her living with us is not a good idea. She likes to be constantly doted on, has no incentive to do anything on her own, including activities with her peers.
But this is just a small flight of not very nice fantasy. Your mother may be clingy and needy but she is in her right mind, yes? And as far as I am aware, guardianship is simply not something that a court would grant in the case of a person who has full possession of her mental faculties.
You can't be forced to accept power of attorney, either, you know. But if you don't want your mother moving in with you, and you believe she will at some point need someone to act on her behalf, perhaps you had better take her to get legal and care planning advice from a professional. Get some sort of grip on the situation before it gets out of hand.
You need to be able to raise your family in peace without her constant intrusion on your space and your marriage. I'm sorry if that sounds a bit callous or uncaring, I don't mean it that way; it's just I can relate to having the kind of relationship with your mother that is based only on her needs and whims, and little empathy for yours, because I'm living it too. I've always felt to some degree like I'm the parent and she's the child.
Has your mom been determined to be mentally incapacitated or is she still capable of making her own health and financial decisions?
An elder care attorney can advise you on how you can best help your mom. I'm my mother's guardian only because it's been determined by her doctors and the court that she lacks the capacity and capability necessary to manage her health and financial affairs.
Even if you do become guardian or POA, it is not necessary that she be living with you. You could still help manage her finances and get suitable care for her without it having to be in your home.
It sounds like she is competent to sign a durable power of attorney (DPOA) for both finances and health care and I suggest you have her do that, if she hasn't already. DPOAs suffice in most situations, cost nothing or very little, and can be changed if and when conditions change as long as the signer is still sufficiently competent. Like a guardian and/or conservator a DPOA agent is "responsible" and must act in the best interest of the DPOA grantor, but usually there are no formal reporting requirements.
I think it would make good sense for you, your sister, and your mom to sit down together with an attorney that specializes in elder law to have them help you with putting some legal documents in place as to how your mom wants her affairs handled both now and if she should ever be unable to care for herself. It makes it much easier right now that she is competent and able to state her wishes, rather than having to guess later on down the road.
I believe if you all come up with a plan now that the three of you agree with, it will hopefully save a lot of drama in the long run too.
If I may gently remind you of this, you originally posted: "My dad has been dead 10 years and she keeps saying she's never lived alone. When I remind her how long it's been since his passing, she reminds me of how she doesn't like living alone. We've never been close, I'm still raising a family and her living with us is not a good idea. She likes to be constantly doted on, has no incentive to do anything on her own, including activities with her peers."
You go on to mention your anxiety about your sister's possible reaction to your mother's choosing you to act for her.
And then you say you just don't want any drama...
And you're *not sure* you want to do this?
If you don't want any drama, then you really, really, *really* do not want to do this.
Your mother is in her right mind. She is a grown woman. Let her figure this out on her own.
As your Mom's DPOA, you are there as "back-up quarterback" for the times that she is unable to make decisions about finances and when she is in the hospital, assisted living, or nursing home and unable to leave the facility to go to a place of business such as her insurance broker, bank, a store, etc. You can transfer money from mutual funds to her checking account, sign checks, pay bills, manage real estate, prepare and file tax returns, and deal with tenants and leased property she owns, etc. It all depends on what your Mom’s DPOA document.
To help your Mom make health care/medical decisions, you need to be her "POA-HC" (Power of Attorney for Health Care). That is a completely separate POA. You act as an “advisor” and offer advice to your Mom regarding health care/medical decisions until your Mom is declared incapable of making health care decisions. At that time you become the person responsible for making decisions about your Mom’s healthcare/medical treatments AND you need to follow your Mom’s “Health Care Directive” regarding the giving, withholding, withdrawing, or modifying of your consent to medical treatment for your Mom.
As bicycler mentioned, you have to petition the court to appoint you as your Mom's guardian, and at the moment, the information that you have given us does not indicate that your Mom needs a guardian, only a DPOA. Also, it can cost you and your Mom thousands of dollars for you to petition to be her guardian. If your Mom owns a business or has a farm or rental properties, then you may need to become her conservator instead or along with being her guardian. Some courts require that the conservator be "bonded" which cost another $10,000+. Once you have been appointed by the court to be your Mom's guardian, you have lots and lots of rules that you have to follow. You have to keep a very accurate and concise record of how you spend your Mom's money and you cannot put her money in the same bank account as your money.
Since your sister has a history of causing drama; I like FM's suggestion that your Mom, your sister, and you sit down together with an Elder Law attorney so that they can make a DPOA-Financial and DPOA-Health Care with Health Care Directives for your Mom.