Hi and welcome to the club no-one wants to be in.
I totally get where you're coming from. I was diagnosed when I was 54, and given 3 to 5 years. That was 6 years ago. I am now running out of treatment options and I'm under no illusions: at best, I may have another 12 to 18 months.
But it doesn't get me down: I have my family and my hobbies, and I enjoy life. I realise I'm very lucky that I don't currently have any real symptoms or pain, and as long as that continues I'll carry on enjoying life, with the cancer being an inconvenience.
I look at it like this: in the original cinema release of Blade Runner, Harrison Ford's voiceover says at the end: "We didn't know how long we'd have together. Who does?" We cannot see or predict the future, all we have is today.
Wishing you all the very best, and keep on keeping on!
Craig