My dad has just been diagnosed with pancreatic cancer and have found out they won't operate. Struggling with intrusive thoughts

I'm devastated. He lives in France and I'm in the UK. I'm going to fly out there as soon as possible. He's being treated in Marseille.

I have very little information so far apart that they won't operate. What should I ask the doctors? What's the most efficient treatment?

How can I help my dad deal with this? The diagnosis took months to come as it started with a lung infection that wasn't going away.

I've had intrusive thoughts the whole time. Imagining the worst and now the worst has come. I want to stay strong and positive for him but I'm breaking down. 

If anyone could share their experience going through this, it would be very helpful.

Thank you.