How can we get mom to go to bed at night and stay there?

She wants to stay up at night, get up early and then cat nap all day long. It is beginning to wear on us. I go back to work next week and need to get her on a schedule. She also gets very restless after supper and often becomes combative and argumentive when taking her medicine and bathing. We have to force the issue to get her to change clothes and bath. Her doctor tells us that she is in stage 6 and has recommended that she be placed into a long term care facility. With my brother moving further away, we now have no one to share the load with. We are in the process of trying to obtain guardianship as she will not give us power of attorney. Any suggestions as her mood swings are getting worse each day and it is wearing on all of us.