"If you are in a non-marital relationship and you die without a will, your partner has no automatic right to any share of the estate no matter how long you have been together. Many people are not aware of this, so it is very important to know your rights in this situation."
For more information, see:-
The situation can change in the event of a breakup however:-
"However, if your relationship breaks down and your name is not on the title deeds to the house, you may still be able to show that you have some ownership rights in relation to the house. These rights are based on the fact that you made a contribution to the purchase price of the house with the intention of gaining a share in the ownership of the house."
Ref:-
I'd recommend a chat with a Solicitor if your friend is concerned. Most Citizens Information Centres provide a free legal advice service and more often than not by appointment only, so ring in advance.