Annie, how I feel for you. DDs can be very strange. I was in a happy conversation with mine recently when she suddenly started telling me how I failed her as a child, wouldn't let me respond and when she had finished resumed our previous conversation.
After I had recovered from the shock. I discussed the conversation with both DH and DS, both of whom promptly disagreed with everything she had said, citing chapter and verse. I still have a very close and loving relationship with DD. It is as if her diatribe never happened. I do not know what triggered it, or even if she remembers saying it all, it was such a short incident.
Annie, ask your daughter about her comments and what she means by it. Can you discuss it with your other daughter? I always find being prepared to talk about things gets me far further than bottling it up and being upset.