Hi Julia
I have used a fantastic company, called Pure Package, several times over the past two years, after seeing one of their adverts in a local magazine. They are a gourmet meal delivery service, based in New Covent Garden Market. Basically, they deliver your meals, and snacks for the day, to your front door in a cool bag. They are really flexible- you can select which days you do and don't need meals for. The food is freshly prepared, really healthy and delicious.
Their web site is
http://www.purepackage.com
You can sign up for your deliveries online, but I'd definitely recommend phoning them to discuss your needs. I've always found them really helpful, and they'll be able to recommend the right package for you.
I send you my very best wishes for a good and fast recovery x