I'm interested in that comparison to light springing from "her clothes" like the morning sun when just above the horizon. It's just conjecture, but I'm inclined to think that the singer is dazzled by the radiance of his lover as her clothes drop from her - just like, if you stare at the sun just as it rises over the horizon, the earth can seem to drop away from the sun. I don't recommend staring at the sun, though. Even just above the horizon it can be too bright for comfort, and that is precisely why it can disorientate you and give the impression that the sun is the fixed point, and the earth is dropping away - and, no, I don't need the astronomical explanation.
Do we therefore surmise that the man enjoyed his true love's favours? Not necessarily.
Was the vision a true one? Who knows?
Was this a last attempt to keep the man from going? Possibly.
Is the image wonderful? Oh yes.