Dad dying

Just joined this site as I was searching the prognosis to my dad's cancer! Doesn't look good for him as he has terminal metastatic colon cancer. He had now been admitted into hospital to try some radio therapy on top of his fortnightly chemo. He has been given the prognosis of 6monthd-2 years but after 6 months of chemo he is fading fast. I'm living in the UK and he is in oz! Do I go back and see him and my mum or wait out to see how he responds to the treatment?  I'm Torn because I don't want him to think I've rushed back oz because u know he is dying!