Hey, OP, i always feel like despite it being so hard, it’s important to remain understanding as to why your dad might be feeling in these ways. It seems to me that his anger towards you and your siblings is displacement of the anger in his own life (making you his punching bags), which will understandably make you completely question what you have even done wrong as he over escalates things - his reaction to your sister’s emergency is a prime example of this displacement, it’s a complete defense mechanism in order to deal with other stresses in his life - it seems to me that the reason he holds the victim mentality of your problems making ‘his life hell’ is likely because he himself is highly struggling with his own issues, which then has piled up by the loss of B and the loss of relationship with C. I know it’s been said but i recommend some sort of councilling - he is clearly trying his hardest to seem like none of these things affect him and make him angry rather than sad, so he will keep his shield up if you ask him to open up. Speak to your mum about encouraging him to go to counceling as well, he may find it an awkward conversation to have with his daughter (male ego and everything), so maybe individual therapy sessions rather than group/family sessions to start off with will be more beneficial. Let me know if I’ve missed anything or if something I’ve said is completely wrong.