Personally, I find the dichotomy between vulnerability and strength sexy as well, and I find it true for both sexes. The best part of a long term relationship is that all of these emotional combinations come out, so you are always adjusting, changing and growing, while fantasy, seems, in comparison, staged and fixed.
Off topic ( kind of): This convo has reminded me of one of my favorite "vulnerable" songs by a male vocalist...Does anyone remember Everybody Hurts by REM?