[MMM]

As Iceinthwater said, one way to get over this is tell girls that you're a little nervous approaching her. From the chick's point of view, this is a turn on, since she thinks "wow, I am such a special little snowflake that has this effect on men." If she is into you, she'll help you along. If not, she'll be inclined to let you down easy, out of the largess of her specialness. Hell, sometimes I'll feign nervousness when approaching a chick so I don't come across as a smooth player, which may trigger the bitch shield coming up. Now go forth and slay!