This thought had actually crossed my mind before you wrote your kissing post, which reminded me of it.
Anyway, this could be totally off base, but in my experience, it can be VERY painful to be touched in a tentative and/or asexual way when one craves passion. If your W is aching for some heat and passion in her life, then she may cringe when you touch her without it.
Of course, when I was S, my XH cringed when I tried to hug him, but this wasn't because he wanted more, but less. It was definitely an invasion of his physical and emotional space.
BTW, it is *great* that you are being honest with yourself about the whole intimacy thing being a big problem for you because of your own insecurities. Though hard, it must feel much better than putting it all on an unresponsive W
