I really really need some advice please :( sitting here crying my eyes out ;(

My nan passed away 2 weeks ago, my partner and father to my child hasn't really been there for me emotionally which hurt at first but I kinda assumed it was hard for him and everyone deals with it in their own way, well that is until tonight.. during an argument he told me that I needed to hurry up and get over my nan dying, everyone dies so what it's no big deal that's life. And proceeded to mock me by saying "Aww I'm so sad my nan died" I just don't know what to do... I told him to leave and he's gone, I'm so heartbroken, sitting here crying my eyes out not knowing what I do next, he's not normally like this, I just don't know what happened or why he said those things. Can anyone help please? X