I Care For a Sick Relative

Hello everyone. I posted a few days ago under the same heading about my grandma. Within those few days her blood pressure has been fluctuating constantly. The fear now is that she may get a stroke. We have cut all salt from her diet and give her the medication at the time she's supposed to have it,but we don't know what's causing it to rise and fall. The doctor explained that it's simply age that's causing it. I haven't been sleeping because she needs round the clock care,but today my aunts are here,because normally my grandma can feed herself at meal times,but today she couldn't. My dad had to feed her. Now she's wearing adult diapers,because she can't walk anymore. It is tearing me apart inside to see her this way and it is becoming apparent that she needs more care than i can provide her. I don't know what to do. My aunts have told me to take the night off,which they've never done,but i suppose it's due to how i'm looking. I haven't slept in days and it is taking a toll on me. I'm afraid to sleep and something happens to her. One of my aunts is planning on staying the night to look after my grandma. This site is my only way of venting and putting out there into the world the way i feel. I feel like my very foundation of my being is cracking.