He has diabetes, has been vomiting for a few days, cant keep food down, so hasnt eaten, says this is the end for him are there signs or s?

This sounds serious: enough in terms of the comment about being "the end for him" . Otherwise having diabetes and/or nausea/ vomiting are two of the most common things that can afflict a human being on this earth since the beginning of time. So it sounds like there are other parts of this story that you cannot share on this medium. Perhaps make a consult with one of our doctors here on HealthTap or take him to ED.