My father has died from pneumonia and septisis shock

My father who was 82 years old has died of pneumonia and sepsis shock which shut down all his organs

He was in a normal ward for 9 days before going into ICU the doctors told me he had a chest infection and i thought he would be home for Christmas

In the first week at hospital i did not see him on the Saturday because i was with my girlfriend who is quite possessive  wouldnt let me leave her, long story. When Sunday morning came my mum called saying he called her asking why i didnt come to see him, i did see him on the Sunday evening but he looked quite stressed as he having some argument with a nurse. On Monday he was quite good but on wednesday they put him in ICU. Im feeling very guilty that i did not see him on the Saturday as i wonder did i add to his death with all the stress i may have caused him by not seeing him on that Saturday? I feel such a weak man for letting my girlfriend control me!