The plucked strings sound like a man itching, restless, pacing the floor back and forth, willing something to go away that just won't. He can't relax. He can't talk on the phone, not for long. The strings slide and glide in a way that is glassy, as if he is trying to walk on emotional black ice. He loves her, it's over, he still loves her, but it's no use. He could go out and yet she would be there, the pluckings now signifying his eye catching this and that, the steps of his walk, the beats of his heart. There is nothing to do but keep loving, because that at least shows he is alive, not just a bundle of nervous moments.
He has lost her, yet he plays it light. He doesn't, like Darin, look back - this is not a nostalgic song, but one that keeps trying, trying, trying to somehow move forwards. But there is no way out, at least for now (Williams' essential warmth means there will be a way one day). The very slipperiness of the song, its goings back-and-forth are elegant and neat, as if the rawness of the experience are gone, and now it is all routine, helpless, he still suffers but at least he is buoyant, proud in his own way to love and keep loving long after there is any real point to it.
There is a more general loss here, of course; the gradual loss of the early 60s, the Camelot age of the New Frontier. It hasn't gone just yet, of course, but by this time (May) the seemingly-placid world of, say, 1960 is pretty much gone. The last Aldermaston march/founding of the CND in the UK, Dr. King's Letter From A Birmingham Jail - these are just some of the more obvious pointers to the intensity of the sixties, and the corresponding need for songs like this (lyrically and sonically) that acknowledge that things are permanently changing, but put them in the most graceful and hummable context this side of Cole Porter (kudos to Pomus and Shuman)...
...my parents not being the easy-listening types (not that this is easy listening, exactly; the poor man does nothing but hit one void after another), the first time I heard this song it was by The (English) Beat; a version so faithful that Williams himself at first thought it was a remix of his own and not a cover. That it works is due to that semi-ska rhythm that is inherent in the song, but also Dave Wakeling's own soulful voice, one which meets the loneliness here head on and understands. ("Mirror In The Bathroom" is just an extension of this feeling, only there is no love for anyone else; just the self. I can only wonder if Williams has heard it.)