It was the late 1960s. She was an up and coming singer and dancer, he was a veteran songwriter from a well known folk band. By a strange coincidence, he looked like Johnny Cash (with whom he sometimes performed) and she looked a bit like Julie Collins.
Her alto/second soprano voice was deemed to be a good compliment to his gruff basso profundo, and his tall cowboy looks and manner (his father was a semi-itinerant horse trainer and her delicate, if unconventional, beauty seemed also to fit the bill. He was planning his first solo album, she had been asked to take over as lead singer of Jefferson Airplane, both canceled their plans.
And so, "Signals Through the Glass," an experimental country/folk-rock album featuring his songs and their vocal harmony was released in 1968, the same year they were made official performers on the Bobby Kennedy campaign trail.
The album, a brilliant mixture of sounds that reminded one of Johnny Cash meets Simon and Garfunkle meets the Beatles, it was well-reviewed but not a great commercial success.
They never again were co-billed, but they were married. Her career was largely limited to the occasional duet with him; he recorded several records and was widely covered, most famously by the Monkeys with "Daydream Believer." His music, especially "California Bloodlines" was internationally successful amongst music critics and D.J.s, but he never made much money.
In the 1990s, she developed brain cancer. Fortunately, it was treatable, but the surgery so bankrupted them that he was forced to auction off his guitar (the buyer gave it back to him.) Their latest C.D. "Darwin's Army" was released a few years ago, although his voice has now aged considerably.
John Stewart and Buffy Ford Stewart are two of the greatest musicians, and two of the greatest people I have ever heard of.