All you ladies are so understanding about mil!!

I am trying to come to terms that my mil will always be in our lives :( i had a lovely relationship with my previous mil and this one we dont even speak she doesnt even know i hate her for what she has done to my partner yet he still tries to keep in touch with her which angers me so much because she doesnt give a damn!! She pretends she does but really couldny care less why does my partner not just break all ties as i am miserable because of this ino its not my place or buisness but i cant help it nor do i want my unborn wee son to feel neglected or unwanted by his grandmother