87F only eats liquids, refuses to get checked

For the last month, mom, 87F, has been living on juice, milk, diluted soup and ice cream, small quantities at a time. She refuses to Ensure. She's lost weight and has become weak.

She is able to swallow pills so we don't understand why she can't eat solids. She has dry mouth. After every liquid she drinks, even after swishing water, she spits a thick, clear mucus/phlegm.

She doesn't want to leave the house to get checked. Blood check showed dehydration, so doctor ordered IV fluids. She says that she's waiting for her death and that there's no point to go to the hospital.

What should be the next steps? It doesn't look like there are enough calories. Does this mean slow starvation? What can we do?

EDIT: She finally agreed to be hospital. This was after abnormal levels of creatinine were found in blood test and a nurse who came home told her that her kidneys aren't functioning properly. The hospital started with abdominal CT scan - tapping on stomach didn't sound good.