I went for a run on Tuesday actually. I had to come back after 5 minutes though because I forgot something. As I came back through the door, my wife asked me what I had forgotten... "I forgot that I can't run!" I replied.
Seriously though, I identify myself as a runner... I had an on off relationship with it for quite a few years but was running for the wrong reasons. It was mainly as a way to lose weight, or to tell myself I had earnt a treat or a night out etc. It's not really sustainable like that. Over the last few years though I have become more consistent and as I say, I now consider myself a runner. It is part of me, part of what I do and as someone said above, it is a very important relationship in my life. Again, like others, I love the mental health benefits it gives me, it's my chance to clear my head and work through things by myself.
I think it helps that I have got quite decent at it, so I can enjoy the results I produce when racing as well as the process of training and socialising. I run with/for my local running club but that is just to mix it up and socialise a bit with like minded people. I am running my second marathon this Sunday in Liverpool so we'll see how that goes but I'm hoping for around 3:10 or so. My other PBs are 18:31 for 5k, 39:56 for 10k, 1:29 for the half marathon.