You were not being argumentative, and I think you actually got the points I was trying to make. I think that's great.
Now as far as getting your wife to define what her needs are:
Remember, you can't make HER do anything. However, what MPT suggested you do is a great path to follow because you are asking her to define her needs in the interests of YOU understanding HER. The intent of this exercise could make all the difference in the world.
When you ask her to elaborate on how she is feeling -- if she ever starts to struggle verbalizing that and reverts to the 'Oh, I don't know, can we drop this?' -- ask her to think about it some on her own, and make a date to talk abou it again two or three days from now.
That way, it gives her room to think, but it also gives her a deadline and lets her know in a non-agressive way that you are willing to drop the issue for now, but have no intention of dropping the issue indefinitely.
