L.F.
Victoria's gave you a great response. I just want to add that even if you become your mother's conservator, you are NOT financially responsible for your mother. So if all of her money is spent, no one can come after you for any expenses she incurs.
Keep in mind that being a conservator is a lot of work. You have to stay on top of a mountain of paperwork and file her taxes for her. If she qualifies for Medicaid, you will have to fill out all that paperwork for her too. It requires a lot of time and organization. If you are already feeling pulled in a million different directions, don't feel bad if you don't think you're up to the task. Good luck.