I lost my dad to cancer (part 2)

J
(I had to cut it into parts because it was too long)
I was confused, sad, and jet lagged. My cousin (who is a nurse) came to meet me at the hospital and sat down with me and asked "do you have any questions? Do you know what's going on?" To which I answered," I have no idea what's going on and I have a million questions but I just don't know where to start...just tell me everything you know, everything that the doctor said." Our conversation was short and to the point. Though I had a million questions at first, my cousins response was the answer to all of them. He said, "jane, I'm going to tell you exactly how it is because you deserve to know. I'm sorry in advance for not finding an easier way of telling you this. Your dad has stage 4 brain cancer. Glioblastoma multiforme and there is a tumor the size of a golf ball on his left side of the brain. It's quickly growing and spreading and the purpose of tomorrow's surgery is to try to safely remove as much of it as possible so he can proceed with treatment. But even after surgery nothing is guaranteed. And of course like with all major surgeries there is also the risk of not making it out of surgery alive, too. If surgery goes well and he can proceed with treatment he could live up to maybe another year. If surgery goes well but the cancer returns, he could have a couple weeks to a few months. I'm sorry." 
My life changed forever in every possible way imaginable the moment that conversation ended. Every minute of every day brought new struggles and changes for not only myself but obviously my dad and everyone else in our lives. Though he made it out of surgery alive, the hours spent on poking and burning and cutting out part of his brain left us with a very different person from the one that went into surgery. Post surgery dad was less patient, less optimistic, less understanding...the man that I've never heard raise his voice suddenly shouted with anger at everyone and about everything. I've seen him cry once in my life, when my parents got divorced (when I was 15) and never again after that, until after this surgery. Suddenly, the man that everyone used to go to when they needed a good laugh was in no mood to make jokes and laugh. I had such a hard time accepting these immediate changes in my dad and felt so angry. I knew these changes were happening outside of my dads control but I didn't really accept that until I saw how hard my dad was fighting with himself (on top of everything else he was battling) to try to remember who he was before the surgery. It took him a long time but he was slowly acting more like the son, dad, uncle and friend he used to be, and we all knew. Though on the outside he was making what seemed like progress, on the inside he was struggling again. Cancer came back quickly, stronger and more aggressive than the last time. It had only been about two months since his surgery but the tumor returned and started spreading to his right brain. At this point the doctors were brutally honest with us and gave my dad two options: 1. Continue taking his medications, up the dose on the pain meds to make the pain a little more manageable, stop all treatments and just spend whatever time he might have left with family and friends at home preparing for the worst or 2. Go in for surgery #2 and try to remove as much of the tumor again in hopes of extending whatever time he has left. The doctors presented these options to my dad on a Wednesday and said if he chooses surgery, that'll be done on Friday. He chose surgery. I would do anything to go back to that day so I can convince him to choose option 1. I know people say "you can't blame yourself. This wasn't your fault. You have to stop punishing yourself with what ifs..." but I do blame myself a little for his final decision on choosing surgery and I do feel like it's partially my fault. So I can't help but think "what if he hadn't gone in for that second surgery? How much more time would we have had sharing conversations, taking walks around the neighborhood, eating delicious meals together, making some last minute memories...?"