Am I too intimidating to women?

I'm a full-time student and I work full-time but I am trying to squeeze a social life into it, specifically dating. I am not arrogant but I'm pretty confident in my looks. I have been told by friends that I have the whole "pretty boy" face going on. I keep in great shape as well. Anyway, I am generally a very nice person no matter who I'm talking to. I usually get along with everyone and end up finding a common interest with everyone I meet. I don't have high standards when it comes to dating so I'm not too picky about who I spend time with.

Lately, I have been trying to meet more girls, either on campus, work, or anywhere (Starbucks, supermarket, etc.). I usually engage in small talk but 1/30 girls ends up being a friendship (most become the dreaded Facebook friends that you never talk to again). The thing that bugs me is that I'm never approached by women, not even in bars, YET, I am constantly in situations where a girl is indicating something with body language, specifically close proximity (practically touching), smiling, and constant staring by some. When I say close proximity, I'm also adding that some girls I've met do this more than once so it's not just a coincidence.

Like I said, I feel great about how I look but I can't possibly look so good that nobody approaches me, can I? Maybe my neutral face isn't so inviting? I know everyone is shy once in awhile but that doesn't mean that one out of who knows how many girls can't say a word or start a conversation.

The other problem I have is girls I actually flirt with where there appears to be a mutual attraction of some kind tend to be in relationships or even married! (and I'm not mistaking their flirting for being nice).

So what should I do about this? Should I accept that I have to approach women and move on or is there secret advice that gets these girls to actually start a conversation? Any advice, specifically from a woman's perspective would be great. Thanks!
Updates
+1 y
When I'm working out, I end my routine with a 40-minute walk, the girls who come up to the cardio machines to exercise tend to get on the treadmill next to me when they have all the space in the world, so this may be a sign of attraction.
Am I too intimidating to women?
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