I literally can't stop asking my boyfriend when we are going to get married

I don't mean to pressure him but i know i am. He keeps saying it will happen but I'm tired of waiting. I want to start my life with him and I want to do it soon. I know he loves me and that eventually we will but I feel like I think about it a lot. I'm annoying myself with how much I bring it up :( any advice? He's 27 and I'll be 27 in the Spring. We've been together for 3 1/2 years