Feel like Mum has been abandoned

First of all apologies if this is not in the right forum. 

My mum was diagnosed with stage 4 incurable/inoperable duodenum cancer in March this year and quite honestly the journey since then has been like pushing water up hill. The waiting time between appointments has been terrible however after 66 days since diagnosis she was given a plan of chemo; once in hospital every 3 weeks then carrying around a pack for the rest of the time. About 10 days after starting this she became so poorly she could barely walk and was admitted to hospital for a number of blood transfusions. She was told to come off the chemo for a week and an appointment with the specialist was booked for Tuesday just gone. At this appointment he was going to discuss with her whether to lower the chemo to just the 3 weekly blast or move onto radiotherapy instead. She turned up for the appointment (bear in mind she isn't leaving the house at the moment due to being weak and tbh I think she's battling with very low mood), waited for an hour only to be told that the doctor had left the country due to family illness. She was told to come back on Friday for chemo, although she didn't really trust what she was being told. After a lot of digging by me we found out that actually he'd gone away a week ago and she should have been told then. Also no one else will be seeing her whilst he is away as they don't feel confident deciding whether to continue with her treatment. So for now no clinic, no chemo and no help. She feels utterly abandoned, like she has been left to die and I don't blame her for feeling this way. Since her diagnosis she has been pushed from pillar to post and has received no real support apart from the couple of time she's been in hospital for blood transfusions.

Given that the GP initially dismissed her concerns and it took her collapsing and being rushed to hospital for any of this to be found I'm not surprised that she and the rest of my family are struggling. I have a family of my own (husband, two young children), a job, house to run which is currently being renovated and my brother and dad are doing a fabulous job of looking after her day to day but I've always been the strong and practical one so I am taking on everyone's worries and organising the financials etc. My husband is a fantastic support but all of this and the worry about what is to come is starting to affect me; I'm bursting into tears at random times, snapping at the kids, eating terribly, and just feel tired all the time. I know this is nothing in comparison to mum.

I don't really know why I'm writing, I guess its good to get it off my chest.