Fil has lung cancer, Dp is shutting me out. What can I do to help?

[TheEndOfTheWorldAsIKnowIt]

Hi my lovely FIL has been diagnosed with lung cancer he was diagnosed three weeks ago and has had biopsies and a full body scan. He is due to have a ct head scan this week and another biopsy next week.
Dp is shutting me out (understandably) he is an only child and this will so hard for him as he is so close to his dad. He is drinking all the time and is just so short with everyone and nasty about people all of a sudden which isn't nice especially as we haven't told our children yet so they don't understand.
I just don't know what I can do to help. I have been making him meals and dropping them off for him or picking him up to come here if he feels up to it but I don't know what to do.
He seems to be going downhill fast which is a shock. He doesn't want anyone in the room with him for appointments and I think he might know more than he is telling us.
I hate this stupid cancer, taking good people away, my friends dad lost his fight two years ago he was diagnosed with lung cancer and passed away three months later. I just keep thinking that FIL might not be here in July

Hi endoftheworld i am the dd of 2 terminally ill parents.Cancer is a cruel illness with many knocks along the way,I hope you fil has good news that this is treatable.Mum has has almost 8 yrs and she was given 1 yr to live they can sometimes do amazing thing with chemo and radiotherapy.Good luck with it all xx

Hi Endoftheworld. What an awful time for you all (flowers).
What you are doing to support your FIL with meals etc is brilliant and will mean a lot to him. He is probably trying to 'protect' you (that's what good dads 'do') by not asking for more support at the moment, and as long as he knows you are there for him, then maybe he will start accepting more help/support in the future.
It's easier said than done, but try not to dwell on the worse, just take things day by day.
You might find some support by looking at the cancer support groups online, Macmillan springs to mind, but you might find them a bit much at present - people vary in what helps them and when.
As Whatis says, there could be treatment that will help, so this the difficult stage where no-one has all the facts yet.