I know this idea is a bit off the wall, but what if Lois is in a plane... you know, bad guys and all that... Superman rescues Lois in the nick of time and sets her down on a nearby deserted island in order to go back for the crew. The plane explodes just as Superman reaches it. Unbeknownst to either of them, the bad guys had kryptonite on board. When the plane explodes, so does the lead box carrying the Kryptonite, infusing the air with particles. Superman crashes HARD down to the water (or the island). Lois sees it happen and rescues him. Only when he awakes, his amnesia from Nightfall is back. (I'm thinking late S1 or between S1-S2... perhaps a story to get her out of Metropolis after her failed wedding to Lex Luthor... something to do with that Colombian* drug cartel story that Lois thought she was nominated for the Kerth for in WoS, to prove that she still has what it takes to be a top notch investigative reporter.) Anyway, the island sand in now infused with sand sized granules of kryptonite, not enough to kill him, but enough to keep his super powers at bay.
I figure Superman's amnesia is only temporary, but long enough for Lois to discover his other identity. Like in Cast Away they can use debris from the wrecked plane (maybe a suitcase of clothes?). Or maybe a sealed hope chest from an old shipwreck has clothes, just so Superman isn't stuck in his suit for the whole adventure.
Okay, I've got Lois and Clark to the island, pre Ordinary People, with no hope of them being rescued any time soon. Now, Go. Shoo. Write.
* The script says Bolivian, but I remember it as Colombian.
***
Also, didn't Nan Smith do something like this in
How I Spent My Christmas Vacation ?
