My H isn't used to being so open either, he's very uncomfortable talking about sex or anything having to do with sex...or our relationship.
The fact of the matter is however; the only way to stop being uncomfortable about something you aren't used to doing is to do it until you are no longer uncomfortable about it. Makes sense doesn't it? If you don't talk about sex w/your partner it feels wierd and uncomfortable when you finally do.
You two are married, you share the most intimate R a man and a woman can share...you should be able to talk about ANYTHING. Think you can give it a try?
Our C gave us an interesting hand-out today (nothing sexual) as an exercise for us to initiate R conversations. I'll post it on here later...there may be others on here who could find it useful too.