With the most recent girl, I discovered that I didn't want to assimilate into her culture and when she told me she would wait for me to change my mind, I thought that she could be doing better things with her time than waiting around for a guy intent on changing his life. Another one started dropping hints that she wanted to get married by not so subtly going out to look at wedding dresses and when I tried to imagine the rest of my life with her, I couldn't. Another one wanted our relationship to be based solely on one kind of sex that I think is pretty hot, but it was like eating your favorite food every day and then realizing that it's best as a treat. Another one didn't see why I'd be upset if she went after my friend, provided she set me up with another (admittedly gorgeous) girl.