Hi Lgi
Firstly I am really sorry to hear that.
Secondly if she were to take out a European policy the majority of these cover the UK anyway and although she may pay a slightly more expensive premium initially but it saves the inconvenience of adding it on at a later date.
The best thing to do would be to look at our travel insurance finder, find a provider she is interested in and talk the situation through with them, they maybe able to come up with a cheaper alternative and advise her of the best option.
Hope you manage to sort something out.
Thanks
Maxine