Can someone please explain the following phenomenon:
You find a girl very attractive, begin subtle flirting, she begins flirting back, things start getting more interesting, you like her more and more, she likes you more and more.
Then, BAM, as soon as a "relationship" begins (or as soon as its begining seems inevitable), you start seeing all these faults in her, don't find her that attractive anymore, want out, think about getting out all the time, call it off, and get a great sense of relief for having "got that out of the way."
Is this because
a) you are thrilled by "the chase", plain and simple
b) you have low self-confidence and want to break up with her before vice-versa
c) you are afraid of commitment
d) a combination of the above
e) something else?