I think I am going to let my fiance know that I do not plan on spending Christmas with her family.
Is there something you're worried about with her family?
I am just worried about being uncomfortable spending the holidays with her family.
Your fiance's family is important to her during the holidays. You not spending time with them shows little respect for her needs. Get past your fears and learn to be around her family.
I don't like them better leave them alone. It's fine if I would visited them one day.
Just know that your fiancee family is also your family. You are going to need to get used to spending time with them since it is important to your fiance. Try to embrace her family the best you can.