Feeling helpless right now

Hi can’t share to much detail but I really want to support my friend his dad is really ill and is refusing medical care. My friend is really worried and went to see his dad today. I was supposed to be seeing him this evening he was coming over mine for a few hours. He messaged me saying he not able to incase his dad need to go to hospital. The reasons are valid for this. I tried saying to my friend I will come over to yours no arguments and if your dad takes a bad turn I’ll be with you and support you. My friend lost it with me and he shouted at me over the phone I burst into tears and my friend showed remorse and calmed down quickly and thanked me but he said I am doing enough as it is. I feel I could be doing more my friend has been amazing with me after my mum passed away taking me to my hospital appointments and buying me a nice Chinese take away after my MRI on Wednesday. Last year he was very ill heart attack open heart surgery and I never once visited him in hospital I couldn’t because of the memories of my mum. I want to be there for him and I really hope his dad will be ok and I just feel so helpless right now. My friend has messaged me apologising for shouting at me and said that we will speak later he also told me to rest and no worry as it triggers my dizzy spells. I can’t help but worry because I know the impact it will have on my friend if something happens to his dad and I really want to be there and support him but right now he only wants to speak over the phone for this evening and nothing else.