You are right. For some reason, your wife is very insecure. Asking you to take sides and cutting off communication for real or imagined hurts is manipulative. Asking you to shout at people is asking you to be as immature as she is. She apparently doesn’t understand that she is creating exactly the situation she fears most: Her bahavior is making a gap between you that will be harder and harder to bridge. No one should ever be asked to choose between the people they love.
I wonder why your wife feels so threatened by your relationship with your parents. Does she, perhaps, not have an equally close relationship with her own parents? Does she feel that she needs to compete for your love? Since you are from different backgrounds, is it possible that she misunderstands your family’s ways and thinks they are being rude to her when they are only being themselves? Or has something happened in her life that makes her feel so unloved that she needs all of your love and attention to feel like she is getting enough? Does she feel she married beneath her and therefore needs you to reject your family in order to be equal to her?
Without more information, I’m afraid I can’t be very helpful. Perhaps you can take a big step back from the situation and analyze what motivates her to be this way. If you can understand her pain, you’ll be able to be more compassionate and you’ll be better able to address her needs. Instead of arguing with her, keep asking her, in the most loving way you can, why she doubts your love. Reassure her you have plenty of love to go around; that loving your family doesn’t diminish your ability to love her.
I wish you well.