I've been in love twice. One was with a past relationship that lasted 2 years and the 2nd one right now.
I've had countless crushes though. . . more like infatuations that have only lasted a month or so. My longest crush has been for 9 months.
I didn't know I flirted unconsciously until a friend of mine pointed it out to me. It comes naturally to me I guess.
Although I'm also oblivious when people are flirting with me, unless they're very straight forward.