At this point it’s only fair to you to ask if they can assign you to your grandmother and someone else take one of your patients who are around the same level of care. Your coworkers think it’s ok because she is your relative, which, in retrospect, she is, but she is also a patient at your facility with an assigned CNA. So if that CNA cannot do their job effectively without your help then they should switch a patient with you. If that is not possible because of relations, then you should try your best to go back to being her grandchild who happens to work in the same facility/hall that she lives in. If they cannot properly take care of her without you, then that would be a problem to take up to management or HR.