Guardianship

We moved our parents from one state to another to be close to my sister after a serious car accident.  My mother was driving and at fault and dad was a passenger.  Both were in serious condition. Dad was already wheelchair bound being a stroke victim.  Now he needs 24 hrs care to turn him to prevent more bedsores.  They are grieving the loss of their home, and dad wants to die in their other home.  Mom thinks she is going to move him back out of guilt, and expense of care.  She also thinks she can turn him at night and care for his needs.  She is 80 and Dad 84.  She can hardly feed herself and has lost alot of weight.  She is not consistent with her meds or dad's meds.  She interfers much of the time with his care and what he can eat.  She has been making plans to move him back and she will not have any transportation like she does now...bus system.

Should we block their way with a guardianship, it would cause a lot of bitter feelings??? I am out of state and I will have to clean up the mess that all of this causes.  Any suggestions?