Hi, Ivan:<br /><br />Although the grammatical construction is similar, in the examples you give, neither suggests a non-grammatical pause. As I understand it, the speaker paused after realized. But a comma placed there doesn't really suggest a pause. It just looks out of place. Ellipses would be better. In a novel, of course, you could write: "... but then I realized," he hesitated, and looked away, "why bother." Or something similar. I don't mind your last example, so long as you change 'realized' to 'thought', but of course the pause is lost.<br /><br />hope this helps.<br /><br />George<br /><br />