I wonder the exact same thing. I wonder if its me, the place I'm in. My guess is that I won't let there be a spark because I'm always the high functioning one in the relationship. Who I am attracted to and who would be good for me are completely at odds.
I'm attracted to (and married) the dark handsome brooding musician. I want a responsible, stable, mature man. Which sounds sexier to you: )
I will say, when I worked at hospice and older people described their love, it was the same feeling for them; that giddy, rejuvinating feeling that make colors seem brighter, ya-di-ya-di-ya.
I think how we go about meeting people now is interesting. I tried internet dating and it was a bust. I met nice guys, but it was artificial and akward for me. I've lost interest in looking for now but I know there will come a time when I will want a partnership again. With spark! :)