Hello Steve,
I have been following your posts with both interest and empathy. You have every reason to be feeling fed up, and financial concerns don't help. I am thinking you might quite like some benefits input from my friend and colleague at Maggie's online centre. You'd need to google it, then join as a member. We are a cancer charity providing psychological and practical info. Tom, my colleague is good at getting to the nitty gritty of what people can claim. You can even say SusieQ recommended you ( that's my username in my day job).
You sound a fantastic man, simply being hit by too many challenges at once. Please don't beat yourself up. The fatigue and problems, both cardiac and prostate cancer treatment related, are taking their toll. They are survivable, but it may not feel like it today.
This is where we all pull together, to lift your spirits and get you through...
Warmest wishes
Sue