If I can just share my view, not as a nurse but as a patient?

Yes, there are people who may lie about having a serious health condition, for whatever reason (and I have known of one person that did this in competition with a friend who did have cancer & subsequently died from it).

However, as a non patient the only knowledge we have about cancer is what we read, see or what a loved one may experience and we don't realise that, not only are there many different types of cancers, there are also many types of treatments & many types of symptoms or side effects. We know that chemotherapy & radiotherapy are usually used to treat cancer but it doesn't work on all cancers - immunotherapy and targeted therapy (drugs) are used for those. We know that chemo causes hair loss in most patients but not all, whilst immunotherapy/targeted therapy doesn't. We know that cancer can cause patients to lose weight & look ill whilst some cancers don't until the last few weeks of life. As an example - a melanoma patient whose cancer may have metastasised to the brain would have immunotherapy or targeted therapy and possibly targeted radiation therapy on the brain tumour(s). The patient won't have lost weight, their hair or even look unwell, but they may present with other symptoms/side effects that aren't usual. Melanoma patients don't look ill until within a couple of weeks of death.

Add to that the fact that every cancer patient deals with their cancer in a way that's best for them. Some become reclusive & don't want to see or be seen, some throw themselves into life to enjoy whatever life they have left, some don't want to talk about their cancer with friends but would rather try to forget it for the moment, some carry on smoking and/or drinking and some prefer to go to hospital appointments alone whilst others prefer company, whether it be a family member or a friend (I prefer to go alone). Also, patients with advanced cancer (Stage 4) are sometimes referred to their local hospice for palliative treatment - this is until they've managed to balance their treatment correctly & then they don't need to go again as they can manage their treatment at home. 

All I'm trying to say is that your friend could be lying but there is also a chance she could be telling the truth. Without asking her outright I can only suggest that you tell her you don't want her to think she's dealing with this on her own and, as her closest friend, what can you do to help her. If she says there is nothing you can do or she wants from you I would take that as a signal to take a step back and see what happens. If she's genuine, she would probably thank you kindly & say she wants/needs nothing from you but your friendship - you should be able to tell if her choice of words sounds genuine or not. If you are still unsure, it may be your head is telling your heart that it's best to step back & see how things pan out. Time will tell, one way or the other. All the best,

Angie (Stage 3 melanoma patient since 2009)

Hello Angie, thank you for your reply. I hope you’re doing well, and appreciate you taking the time to reply to me. It’s been really hard journey going through this as i feel i am horrible for even considering this, but as she is known to be an (undiagnosed) pathological liar and someone who often cries wolf, it’s not been easy, as i want to believe her and that she is doing all she can. I think your right and it’s time I ask her outright, If she really is sick i want to be around her and help her, we are both so young and i want to make our relationship what it once was again, even if me helping means stepping away. I wish you all the best and again, thank you