Mum has Ampullary cancer just been told has only months left there’s nothing they can do for her.

Hi my mum has Ampullary cancer wee were told yesterday that there is nothing they can do for her and said she has months left . A recent scan has shown a shadow now on her liver they said unsure if this is cancer spread or just scar tissue but I doubt it as previously was all clear. I am absolutely heartbroken and I don’t know what I should say to my mum as trying to not break down in front of her as sets her off ! But at the same time I want to talk to her about everything.!
I would be so great full if there is anyone who could give me any advice on how and what I can do to support my mum. I am writing this but at the same time I feel like it’s not sunk in yet x