Why do I run?

I have had a lot of friends and relatives of mine ask me why I run? Initially they thought it was to prove a point or to achieve some suppressed dream of achieving the unachievable or that I was simply losing it..
The most interesting remark was after I had completed my first marathon, almost everyone thought now that its done, I would get back to 'normal' and get over the 'fad' of running, as the goal had been achieved.
Now that I have completed by second, third..... They seem to realize that running seems to mean more than just a form of exercise or a fad (as its impossible to continue with a lone sport unless one really enjoys it). Coming back to the original question of why run - the answer, other than the obvious things about health and fitness, is the fact that it gives me time with myself, give me quality time to think, it gives me a high, helps me touch & push my endurance level limits every now and then, gives me the courage to push the envelope, it teaches me to be patient & consistent (practicing the same thing day in and day out and trying to get better with each passing day, to realize when I need to take break - ability to listen to my body) and gives me the required motivation and opportunity to travel to different countries by participating in different marathons. These are just the things that come to my mind now on what I get from running. I hope I have been able to answer the question.
I have till date only participated in one marathon outside Bombay and I did a fab time. So I hope to repeat it in my Singapore marathon! To better myself with each successive marathon is another motivator, till date I have been able to do it and hope to continue doing it in future as well...