My dad has just been diagnosed with blood cancer. Im petrified.
Ah, I've got multiple myeloma so I'm not sure I can be of much help. Never even heard of your dad's cancer, so I can only wish the best for him, you and your family.
Hearing of a diagnosis is pretty traumatic for all concerned initially. We, my family and I got all the information we could and talked, cried, argued and laughed. I became very ill very quickly; the family all rallied round and were/are my carers, my wife being the main one. They all became advocates for me, someone always accompanying me to the hospital, helping me move about, all sharing all information about my condition and asking relevant questions.
They cook for me, encourage me to eat, exercise as and when I can etc. In fact, without them, I'd be dead already, I literally owe them my life.
You'll hear about being strong, something I don't really get. In my opinion, all anybody needs to be, is sufficient to the moment. It's not necessary to be constantly positive, it's ok to be sad. It's even better when a moment of sadness is shared. Just as when a moment of happiness, and there will be some, is shared.
The more you can share, the more you can support and share the moments. Forget about big pictures and how much time is left, live for the moment.
That's the most important thing to me; that my wife and children live their lives and don't make everything about me.
You will need respite from time to time - to be on your own and have your own moments, or to be with your own family and share moments with them.
Feel free to ask questions here or just vent your feelings if that's what you need.