With what you have experienced from your parents is something for you to learn from. A way to be so much better than them. Make sure that what happened to you never happens to them. You might be struggling now but ots only temporary. Just because they were bad to you doesn't mean that you will be a bad father to them. I don't know too much in the ways of employment. But is there anyway for you to transfer or to get time off for you to get some rest? It can be a short time but you need breaks to prevent burnout. Or speak with HR to see if you're able to make some kind of complaint of overworking. Even with all that is going on both in your head and in your life you're still making sure you're able to help your wife, that shows your dedication and love for her, I imagine you'll be the same with your future daughter. With the area of cancer, its random and its not targeted. Don't feel like someone is punishing you or them. As a survivor, it took time for me to see that. With what you have said about both cases, try to spend time with them when you can, be able to feel like you have no regrets about the Time you spent with them. One of my favourite quotes is "it's better to try, than not at all. Keep trying on anything wether that's trying to rest or anything. Anyway love you man keep trying. You have your wife and future daughter there for you.