I had a similar experience, though not on the same scale.
When my grandmother went into a home, my mum and her sister gave me an old battered suitcase that had belonged to my grandfather. My grandmother kept all her paperwork etc in there (I had been looking after all my grandmothers paperwork for years).
Anyway, there was a lot of info in there about my grandfather, none of which I knew about as my grandfather died when I was very young, and I never knew him.
Anyway, armed with this backgroud info, I spoke to all 3 sisters (my mum and her 2 sisters) separately and made notes and then sent each one a copy of their transcript, so that they each could confirm what they had said.
I then put all this info into a report together with other info I had found from my research. It was cause for discussion, as all 3 had different points view and had different memories of their father. As a matter of principle, each disagreed with the opinion of the others.
I tried to point out that opinions are objective and personal. That you cannot disagree with an opinion. I came to the conclusion that it is MY work, they don't have to read it. And if they do and disagree, the door is wide open for them to comment and make amendments.
On the other end of the scale, I found out that my dads uncle, who got me started with all this stuff, was actually born 5 years after his dad died. It was only when I was going over the report again that I realised. I had already sent out the report to all family members. Whoops
However, he was fine about it. Facts are facts and you can't change them. Not a bad attitude for an 85 year old.
I'm quite thick skinned when it comes to family disagreements, so it doesn't bother me much. I would say though, that it sounds as if your family has upset you after all the trouble and effort you went to, having consulted them first, with no ill intention. Families do however tend to fall out over the daftest things, which are laughable when you look back at them later.