Not that I've actually felt that spark recently, but I have thought about it a great deal over the last few years and thought I'd post my conclusions. First is that romantic love, when it is in a healthy relationship, is fantastic material for philosophical/spiritual progress. This is because the moment of eros (romantic love as it is felt) pulls us out of ourselves in a very real and concrete way. This feeling, if we are able to allow it, will grow into agape (love that is spiritual, not sexual, in its nature). And it is experiencing and understanding agape that opens us, both intellectually and emotionally to the whole of the world.
Think about that first kiss. It almost physically brings you out of what I would call your'self', that thinking/analyzing part of your existence. Thought just stops in that moment of romance. Experience is DIRECT. And think about it. It is one of the most Vivid memories we usually have, exactly because it isn't mediated/muddled by all kinds of conceptual thought. It is direct. The problem is that our analyzing mind creeps in and makes us worry about this or that and we lose touch with the moment; the romance is lost.
It is not that the thinking/analyzing mind is bad. In fact it is essential to our life, our existence, and our happiness. The problem is our controlling it, using it when it is useful, and just living in the perfect, eternal moment when that is appropriate.
That kiss brings us into the moment; understanding the way our mind has come to this moment and how the mind can lose the moment gives us the power to remain 'in-the-moment' throughout our life. This, I think, is enlightenment. It is knowing the experiences of life directly, USING analysis when needed, but not being overrun by it; and likewise being fully aware in every moment, not lost or 'just day dreaming' ever.
Until we've reached that, we will inevitably react to the world, sparks of romance included, with the unskillful emotions of greed and/or aversion; but just knowing that we have a choice in the grand scheme of things is a start.
On a lighter note, I think the first thing I do when I get back to Montana is 'find myself a woman' as we say in Montana - (knowing full well romance doesn't exactly work that way). Until then I'll just try to live in the moment by way of philosophy and meditation... and Beethoven.