The Ramblings of an Accountant

Can anyone here help me with a quote? I'm terrible at these (especially exactly how they go - so expect this to be a rather random paraphrase).

Marriage is something people do when they run out of things to say to each other.

As I say, this could be a whole half-hour speech with quoting person playing the part of both parties. Or it could be shorter than that quoted!

cuvalwen was sure it sounded like dear Oscar, but I've got a feeling it might've been a sit-com or similar. Of course, it could've been a sit-com rehashing one of Oscar's lines. Well, they are eminently quotable, after all.

ETA: With many thanks to girlyswot, I can now categorically state that it's from Four Weddings and Funeral. You did all know that I'm hopelessly uncultured, right? The full quote is:

Gareth: I've got a new theory about marriage. Two people are in love, they live together, and then suddenly one day, they run out of conversation.
Charles: Uh-huh.
Gareth: Totally. I mean they can't think of a single thing to say to each other. That's it: panic! Then suddenly it-it occurs to the chap that there is a way out of the deadlock.
Charles: Which is?
Gareth: He'll ask her to marry him.
Charles: Brilliant! Brilliant!
Gareth: Suddenly they've got something to talk about for the rest of their lives.
Charles: Basically you're saying marriage is just a way of getting out of an embarrassing pause in conversation.
Gareth: The definitive icebreaker.

*g*