Average life span after Whipple for chronic pancreatitis

What is generally thought to be the average life span for some one who has had nearly all their pancreas removed with a Whipple Pancreatoduodenectomy
In hospital I was told it was around 5 to 7 years.
I am still in enormous pain 22 months after my Whipple and the huge amount of narcotics I am on aint really doing anything except stopping me crap for 10 days at a time.
I have tried to get answers from my surgeon as to whether my pains are life long post operation pains.Or are these worsening pains caused by what's left of my pancreas going rotten like the previous bit that was junked.But I am definitely not on his priority list for information that's for sure,as he has made it abundantly clear that he has done all he can for me and that I should basically just be glad that I am still alive.I have asked for a description of how my guts have been restructured,so I can try and understand my pains and discuss it with my GP.
But this simple request seems to be a no go for some reason.
The only difference in pain is that the feeling of boiling hot water across the top of my chest is not quite as bad as before the Whipple.
And although I still have massive chronic pain all over my guts I no longer have the same horrendous symptoms that I had.
Before the Whipple it felt like my insides were being gnawed at and eaten by ravenous rats with red hot electrically charged teeth.
Now the pain is reduced to ravenous mice.But the little basterds are still plugged in.