I don't know if this will be helpful, but one thing I have learned is that using words like "we" instead of "you" can keep someone from becoming defensive. (ie: "I was hoping we could work on this problem," as opposed to "you have a problem."

Another thing that's worked for me over the years is to use the phrase, "I feel like," or "it seems to me," rather than just making an accusation. It kind of softens the blow and allows the other person to hopefully understand where you're coming from a little better.

If all else fails, maybe you could write out your thoughts and present them that way? I know it's easier for me to be able to think things through ahead of time and organize them on a piece of paper. Plus it gives the other person time to process everything without having a knee jerk reaction.