I remember a story where Clark moved overseas (London, I think) after breaking up with Lois for her own good. Both of them are at a charity event in Metropolis. Lois has a fiancee who can tell that Lois and Clark still have feelings for each other, so he lets Lois go. I remember feeling kind of sorry for the guy, even though Lois and Clark get together in the end. Is that the story you're looking for? If so, maybe those details will jog someone else's memory.
That's Old Flame.
Mike