If you notice, you signed your letter to me, 'Too Good. ' If you think of yourself as too good for the men you date, I am sure that they are reading your unconscious signals, which invites them to back away from you.
Keep in mind that most people don't feel too good about themselves; so how can someone who feels like he isn't 'all that ' even dare to have a relationship with someone who is so much better than he is? You need to first examine why you have this 'better than thou' attitude about yourself. Is it actually an unconscious defense mechanism that your psyche has devised to keep other people away from you?
In other words, are you actually afraid of becoming too intimate with others? This 'too good' defense may actually serve to 'skunk' people away from you, thereby keeping you alone and safe. Understanding is the first step to moving beyond this defense. If you do, indeed, fear intimacy, then address the problem head on. Figure out where the fear began. Did you watch your parents destroy each other? Did you vow to never allow yourself to get close to another person? Are you afraid to be abandoned because your parents abandoned each other or you?
Once you identify the source of the fear you are on the path to healing it. When you no longer need to keep other people away from you, this 'better than thou' defense will vaporize all by itself, and you will find your very desirable self having to beat them off with a stick.