Okay, you clearly don't get on with your cousin so I'm going to put that to one side for now; some people just don't get on.
You say that the other dog bit your dog, and your dog started growling. This sounds like the kind of situation that two people see very differently:
Dog Owner 1 "our two dogs were play fighting when the new one starts growling really viciously at mine. My dog was scared. I stopped the fight and reprimanded the dog that had shown aggression. Then I calmed my dog down"
Dog Owner 2 "our two dogs were playing and her dog bit mine. My dog growled in self defence, but then she hit my dog and petted hers."
Do you see my point? Without all of us being there we can't judge which dog owner really did the right thing. Maybe neither of you?!
So, back to your cousin. You're not going to be best buddies, and quite possibly she has lots of grievances against you that she's venting on a forum right now but the world is full different people. Keep to your own space, don't try to avoid her nor to be with her. Just accept that she is alive and in your family too.