Good for you giving it lots of time. It sounds like you have a ways to go to get open communication going. You are on the right track, just keep communicating like you want to be communicated to. Leading the way to a style of communication is all you can do. Telling him that you are communucating in a way that you want him to communicate is part of it.
My husband and I took a communication course (non-violent communication) before we got married and it has been invaluable. We use it often and it has shaped how we deal with everyone in our lives now. Sometimes when things get heated we remind each other that we are not being gentle with each other and do our best to get back to the techniques we have shaped to be our own. Perhaps this is something you could consider.
We took a parenting course about communication too and it was more of the same. We use the same techniques and methods with out son and he is growing up to be an excellent communicator. It is fascinating to hear him express himself to get what he needs now that he is older. Really, poly aside, I think all parents and relationship dynamics could benefit from some education in the communication area.... it really is the pillar that keeps a relationship of any kind grounded and strong.
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