Hey - we've had similar news, but with kidney cancer. It's horrible and i'm so sorry.

I've been doing a lot of research and speaking to those I know have overcome advanced cancer. They refer to it as living with cancer, creating a constant anti-cancer environment. Basically ensure your body has all tools in place to fight the cancer alongside medical treatment. 

1) Diet overhaul. No sugars, red meats, processed food. All the green tea. I ordered a few books on this. 

2) Keep heartbeat up. Encourage your husband to take an hour exercise a day if he can, even if long walks. 

3) Look into clinical trials - speak to his doctor and see what the options are there.

4) Research treatment in other countries, where clinical trials have already progressed and there are more treatment options (if possible)

5) Positivity. Easy for us to say, nearly impossible to do. Frame this to your husband as something you'll tackle together, you're learning a lot, treatment has improved massively past few years, diet overhaul will be good for all of you etc etc. It's supposed to make a huge difference. 

6) Ask him what kind of environment he wants to be in. For example if you need to de-clutter, or figure out a space he can have for himself.

7) Whatever treatment he has - DO YOUR RESEARCH. I cannot stress this enough. When my mom had cancer, the doctors were useless and didn't remedy any of the side effects (e.g. awful constipation) which gradually made holes in her bowel. That could have been easily prevented at the start. So make sure you ask the doctors 1) what the side effects of treatment will be 2) which ones could have a longer term impact 3) how will they try and reduce that longer term impact in real time. 

8) Research his doctors. You want top of their field doctors for this. Make sure they're known for how brilliant they are in their field. The ones who are brilliant can give you advice about other treatments and trials etc.

9) Fight. I hate to say this but NHS management processes are (in my experience) awful. Not the doctors, not the nurses, the management. Do NOT wait for them to just contact you. Get the numbers of his doctors secretaries, the main departments. If there is ever a delay, you kick up one hell of a fuss. Threaten legal action, threaten to get newspapers involved etc etc.

With the "changes in him" - I've found that depends on the personality of the person. For example, my mom had cancer years back and she was immediately depressed and almost in mourning. But my mother is highly strung. My dad has recently been diagnosed with stage 4 kidney cancer and his reaction has been more "embrace with positivity and figure this out". 

I've got my dad a book called: Anticancer: A new way of life. It seems like a good one.

You can do this - you have to just be a rock, do the research and form a plan. You've got this.