I don't want to upset you but the problem may be that you can't really get more comfortable with this because it is not in your nature. I don't' encourage either partner to do things in the bedroom that they are uncomfortable with. I know you want to do it and that's fine but if you are anxious doing this it may not be something that will happen. When you are so uncomfortable that you can't experience pleasure then it is interrupting the experience. Find out how important this is to him. He might really feel like it would be pleasurable but it is not essential. You may be focusing on this and in time it may become easier for you. I don't think he is trying to change you but I think he has a desire that may not be possible right now. Talk to him about how necessary this is. Maybe he is fine with just doing it himself.
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