MIL help

My mother in law attacked and threatened me recently, it has made me fear for my life as well as my child’s life. Just the thought of her now stresses me out and makes me have severe anxiety, my chest tightens and it feels as if my Herat is pounding out of my chest, while simultaneously becoming very nauseous. I told my husband that I dont want anything to do with her and I don’t want her near our child. We are supposed to go to my SILs graduation this spring but my husband doesn’t want to now. All because he doesn’t want to tell his family what his mother did, because he believes it’ll tear his family apart and he will be disowned. Mind you my sil does not live with my mil(mil lives in a different country), and sees her but once a year. My husband think I am being selfish and manipulative because I don’t think he should hide what his mother did to me, from his family. I’m beyond furious and upset that he won’t tell them IF THEY ASK why our son isn’t allowed near her, and that he is still protecting his mother over me. That he is defending and protecting the feelings of the person who attacked and threatened his wife. I don’t know what else I can say and do for him to understand that this is wrong on SOOO many levels. I need help