My read is that they were just biking along. Not sweating it. And she moved left at the wrong time (I wished she had moved right so that would sound better). Bang! Old people fall hard. You can't avoid everybody all the time. Maybe they could have given more room. Maybe they could have gone slower.
How many peds have you passed this year? Every one of them could have darted into your path but they didn't. I hope her family understands but I doubt it.