They are only displaying their own weaknesses, but I feel for you.... I feel I have bridged a few relationships in family in my life, maybe not entirely healed, but one day my nephew wanted to sit with me and tell me how much he hated how his mother (my sister) talked about me, I cautioned him, you know you are talking about your mother, my sister, there are things that you can't unsay. It's common and sad siblings and family talk down to another in family. I wonder what my sister would have thought if her son was confiding in me his sensitivities, as he understood me as sensitive?
I hope this passes for you. It has for me.