How do I tell him to get his shit together nicely?

My boyfriends been being a rea douche lately, and I'm trying to be the bigger person and keep calm. I'm constantly asking him what's wrong, trying to reassure him show him love yada yada but all I get back is him being a dick. I fee my self sooner or later hitting a breaking point and not giving to fucks and being just as pissy to him as he is to me , but I find that petty and don't want to create more issues. So how do I kindly tell him he needs to stop being a dick to me when I'm only trying to help him out cause it's pissing me off and I'm not gonna take his shit anymore?
How do I tell him to get his shit together nicely?
Post Opinion