Looking for a way to set boundaries with mother

My mom recently told me that my cousin (we’re both in our early 30s) same age as me is having a baby. My parents are from a different generation and they insist that that’s very late (I don’t have any kids yet). My mom found out from my uncle (she has strained relations with that side of the family in my perception because she criticizes them every chance she has and has grudges from childhood) and told me that to her it’s half as likely to be a lie. I told her it would be nice to give her best wishes to her niece any way. Skip a few days my mom tells me that my uncle told her that I spoke with my cousins 2 days ago for half a day. She insists he has no way to get in touch. Cousin is in another country so I messaged her and we did respond to one another over half a day. My mom (who is also in a different country from me and my cousin) got upset over the situation and let the group chat with me and my dad. I tried to call her once but she didn’t pick up. I talked to my dad and he initially told me that that side of the family has set me against them. I chatted with him and clarified that I have boundaries and I didn’t want to retell my conversation and I don’t need a reason. I think my mom took it as a breach of some sort of trust.How to I help my mom understand that she need to be better at nurturing relationships (less point blank criticism) ? Did I breach her trust? I encouraged her to congratulate her niece while she insisted it ‘50/50’ likely to be truth.TL;DR: my mother is upset with me because I didn’t share a private conversation with her? I insisted that she makes contact with the person herself. How do I help her be her better self? via /r/raisedbynarcissists https://ift.tt/31l4uHV