It's too early for you to be involved with her at the funeral, or even go to Xmas at her family's house. Try to have your own Xmas at your house alone with her. Try to be understanding she might be the one having to make funeral arrangements and contacting other family for the funeral. And be there for her if she needs someone to listen.
I have a long time interest in psychology, specializing in relationship dynamics for 30 years.
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