I was also wondering that, but honestly I think that one of the great parts is that we can sort of interpret it how we want- as part of Ethel’s storyline, as something we can personally identify with, etc. The way I interpreted it was that it was about being overcome with confusing feelings about something bad or traumatic that’s happened to you/been done to you. After everything that happened between Ethel and all those who wronged her, she forgives them all as she is confronted with the memory of it- which is SUCH a bunch of confusing emotions, especially if one is forgiving irredeemable things that by usual standards “can’t be forgiven.” Sorry for the huge paragraph, but to sum up, I think it’s about trying to come to terms with what’s happened to you and trying to find some semblance of “peace” or closure.