Oh hun big big hugs, what you're going through is so very difficult. Like Mini, I nursed my mum when she was dying from cancer 10 years ago. Mum was amazing, never got angry or upset with what was happening to her but the rest of the family were so hard to manage. Men are completely rubbish (usually) in this sort of situation and I found myself being nursemaid, cleaner, making all the meals, doing the washing, and so on, because my dad, brother and his two sons couldn't cope with it all, and got angry/upset at me for no reason and in completely unpredictable ways. And on top I had to be emotionally strong - so I know exactly where you're coming from.
All you can do is keep going, day by day - and make sure you talk about it to friends who can give you a cuddle and support when you need it - and rant here too, obviously xxxxx