I sure do identify with your situation, and I think the other responder on the list has some good suggestions for you, like the clear path to the bathroom & the night light. In my work to help persons with memory decline, I often observe the physical therapists who work with people to practice getting up out of bed. Generally, they will work with a person to practice the following steps: (1) After awakening, sit up against the back of the bed, (2) Then, swing your feet over the side of the bed and sit there for a few seconds, (3) After that, reach for your walker or cane, (4) Slowly stand up and wait a few seconds, and (5) Then, walk to the bathroom. When I first observed a physical therapist working on these steps with a patient at a long-term care facility, I thought, "This will never work!" However, after two weeks (of daily) helping the person to practice these steps--she started doing them automatically! While I am not a physical therapist, I have seen this kind of practice work well. I noticed that the therapist focuses on showing the person the steps--rather than relying on the person with dementia to remember the words/steps on his her own. I think a key for you might be to think about how you communicate with your mom. Then, you might try to build the steps of getting up from bed into your own style of communication with her. In my experience, just getting a person to swing his/her legs over the side of the bed and sit there for a few seconds before standing up can work wonders!

Best wishes to you!