Hi Brooklyn 56, thank you for openly sharing this difficult situation you and your sister are in; it is heartbreaking. It is certainly normal to cry and feel worried about your mother and it can be stressful not to be able to visit her in the nursing home during this time. You may want to explore alternative safe ways to stay connected if she cannot hear you on the phone (e.g., some hospitals offer the “email-a-patient” service, where you can submit a message online and the staff will deliver it to patients the next day).
I am glad you are trying different strategies to help you cope, that shows a lot of strength and determination on your end. It can be helpful to reach out to loved ones for support, and if you feel like you still are not coping well, you may need extra support from your family doctor or other health professional.