Today my friends and I went to a chip shop. Which sold both Halaal and Haraam food? I got just chips and my friend got chips and gravy. She thought that the gravy was Halaal but then I told her stop that is Haraam. She then replied by saying "well I've got it now...so I have to eat it and I was in shock. I was really upset and angry do I did not speak to her; this is because she did not feel bad about eating the Haraam gravy. Could you tell me please this is Haraam isn't it? I mean eating Haraam when I told her it is. Could you please give me an answer to this because I really need to know the exact answer?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

It is most likely that in non-Muslim countries they do not observe the religious requirements whether or not the slaughtered animal is lawful. The same thing applies regarding the method of slaughtering. They usually electrocute the animal while they may slaughter the pig and the like. So a Muslim has to take precautions and not eat except what he is sure is lawful, either slaughtered by a Muslim or by a person of the people of the book according to Islamic rites. Therefore, if your female friend is in doubt whether or not the meat of that gravy is lawful then she was wrong to insist on eating it and you really did well by advising her. As regards cutting relations with her, this is permissible if you are sure that it is more beneficial than not cutting ties. 

Allaah knows best.