i can't get my bf to talk about sex

We've been together 2 years, we always have good sex but it's getting repetitive and I want to experiment! I've asked him several timea what his fantasies are and if there's stuff he wants to try but he says he doesn't really have any and he's happy with our sex. I've slowly found he likes to be dominated and anal play and I've worked that in even though it doesn't come naturally. I LOVE being dominated. I'm really tired of always being in charge, initiating, etc. How do I get him understand I want to try different stuff?