But it was the daughter's choice to marry into that gypsy community, her choice of husband. Unless she wasn't mentally capable of choosing her own partner, the man she picked is someone with qualities that SHE appreciated.
If a girl from another culture married into a "traditional British" family, and was accepted and welcomed as a daughter-in-law, and her own family then objected strongly and continued to denigrate the "traditional British" way of life for years afterwards, I think the girl's husband and his family would be justified in being annoyed, and saying so.
THAT is the other side to the story, and that is the kind of thiing that many posters have pointed out could be behind a lot of the estrangements. These posters are not trolls, not people wanting to hurt the estranged grandparents, just posters who suspect that some of the stories have become a bit blurred from years of repetition, and the grandparents' own part in them could have been a bit airbrushed in their minds.