Song on the Radio.

In the soundtrack of his life there, that song clearly represented that particular time.  Not only because of its lyrics, classically appropriate as they were (although he was never really sure if he should think of them as directed at him or from him), but of when it was played. It was played a lot, as it was at the top of the charts then, but it seemed to be played only at moments when it was particularly relevant.

Of course, there were a lot of those moments, but there were a lot of other moments as well, and it never came on the radio during those. And the radio was almost always on. Nor is it that he just didn't notice it; when that song played, he noticed it. And when that happened, it was one of those moments. It did freak him out a bit some times, although he knew it was merely strange coincidence.

When that time ended abruptly, or so it seemed to him, that song's time on the radio ended as suddenly as it had begun, as often happens with hit songs. To be sure, it was still played, but not nearly so often, and when it did, it was just as likely to be during one of those other moments. Eventually, he just didn't notice it anymore.