Hi.
I agree with trying CBT, it is really good. I had similar problems when my children were young - I didn't want them to leave my side in case terrible things happened. My doctor described it as extreme anxiety. I would worry if they crossed the road, did PE, had colds, anything would send me into a panic. I would make sure we had every medicine available in the house, and the car always had petrol in it, in case they had an accident and wanted A&E. This never happened, I've been lucky, they are healthy. As they got older, and regular visits to my doctor and counsellor helped, I realised they have to lead their own lives, and I should stop worrying so much.
Of course, as a parent, I don't think the worry ever goes, but I have learnt to live with it, and be more relaxed.
One way of coping is, I would read a book or magazine, knitting, cooking, gardening, anything to take my mind away from the anxiety. One of my friends began doing jigsaws.
Can't offer any more advice I'm afraid, I hope your friend gets better, I think a visit to the doctor would certainly help. There's no miracle cure, I wish there was.
P.S. I know someone who was born early and weighed 2lb at birth, is now aged 56, and in good health. Her mum used to worry about her, as she was born prematurely.