Sex talk

So I’ve been with my boyfriend for about 4 years now, and lately I’ve been trying to talk to him about our sex lives, because there’s things I wish we could change I.E. being more adventurous, and every-time I try to talk to him about it, he gets defensive and angry. And finally he tells me that he doesn’t want to talk about it because that’s how he was raised, but it makes no sense. We can HAVE sex but we can’t TALK about sex.

Ladies I need your advice on this!