I definitely would keep blogging if I couldn't get comments, because I'm a writer first and foremost (heck, I used to keep a diary! Who sees that?). I kind of wonder, though, about the value of commenting myself. How often do we all comment because we're really interested in what a blogger has said, or because we're looking to drive traffic to ourselves?
For example ... do you comment on a great blog post -- even if you'll be the fiftieth or hundredth commenter, and probably nobody will see it? I have to be honest. Usually, I don't.
I would definitly keep blogging if there were no comments. I do love reading what my readers have to say forsure, but I write just as though I was wrighting in a journal, only I dont run out of ink, or get a hand cramp!! I love blogging and will continue, with or without comments.