told my family about reunion - it didn't go well

I'm so sorry you are going through this! Do you think maybe she is threatened (like your mom) about being replaced? My sister and I aren't close, but she is jealous of people I am close with (even my own hubby and son) because I am close with them. I would suggest giving her time, then maybe invite her over for a chat and see if she's willing to at least talk about her feelings - without you getting defensive or upset. Letters, emails, etc cannot properly display our emotions. Talk it out if you can. Sounds like she's battling her own demons and isn't dealing well. So sorry.