Worried about my friend

My friend was diagnosed with metastatic breast cancer in November 23 - the cancer has spread to her lung and possibly lymph nodes. Treatment began in December and she is on Letrozole, Ribociclib and Zoladex. She had to have a 3 week break after her first cycle of Ribociclib instead of 1 week and the Oncologist has now reduced her dosage of Ribociclib as she wasn't managing it very well and has had to have a couple of blood transfusions to improve her blood readings.

She had fluid on her lungs which was being drained 3 times a week originally, however that is now down to once a week and they are removing less fluid each time - which I thought sounded positive.

At her first review with the Oncologist at the start of February she was told that her cancer markers had reduced - again sounds positive.

A couple of weeks ago her cough came back, and then she was unable to get a blood transfusion as they were unable to get a cannula in her veins. When she went back the next day they were still not able to and she also had a temperature.

She had to be admitted to the hospital and they have done x-rays and CT scans to try and find out what is causing the cough but nothing has shown up. She is still in the hospital now.

She has been on an antibiotic drip for a few days and her temperature is back to normal, but she is still coughing and her white blood cells are at the lowest they have ever been.

I am so worried about my friend - I don't understand what is making her poorly - is it the cancer or could it be something separate?

I wonder if anyone has experienced anything similar? 

It is all so frustrating as things had taken a positive turn but now it seems less positive.