Trying to ID a classic B&W movie about 2 couples stranded for Christmas in a cabin/lodge due to a snowstorm. The couples are mis-matched, and in the end the right couple gets together. I can't remember the title or actors, if anyone can help.
I did a bit of searching and here are some I found with varying twists to that theme, it looks like they had a lot of fun with that in the Classic era.
The Facts Of Life (1960) - similar type of plot I think, but in color. Haven't seen it yet
Two romantic couples are each married to different people! They really DO love each other. At the beginning Kitty thinks Larry is un-funny, unendurable, and unrelenting. Larry thinks Kitty is just plain dull. Then three couples cancel their trip. Kitty and Larry are ALONE! At the hotel they go under the silly names of Mr.George Washington and Mrs Martha Washington. Then they fall in love while going fishing. When Kitty caught her first fish she kissed Larry. Kitty and Larry started to spend a lot of time together. Then Kitty writes her husband a letter telling him that she wants Larry, not him. Then Kitty and Larry get into a big fight. They both see that they are making a big mistake. They thought it wasn't right to have an affair at their age (they were middle aged).
We Were Dancing (1942) - less like your description than the other suggerstions
Princess Victoria 'Vicki' Wilomirska and Baron Nicholas Eugen August Wolfgang 'Nikki' Prax are expatriate European nobles with no assets or property except their aristocratic pedigrees. They have become professional house guests at homes of socially ambitious nouveau riche Americans who want the prestige of playing hosts to these titled spongers. However, when Vicki and Nikki want to get married, they find that married royals are not in demand as eligibly unmarried ones. Ultimately one of these socially attractive, unambitious bluebloods will have to do the unthinkable and actually get a job.
And So They Were Married (1936) - sounds to be the closest to your description
A bitter widow and a grumpy widower find themselves stuck in a hotel that is cut off from the outside by a snowstorm. Although both have no intention of getting married again, they begin to fall for each other. Their children, however, are determined to see that the "romance" never gets off the ground and do everything they can to see that they are kept apart.
Idiot's Delight (1939)
When song-and-dance man Harry Van returns from World War I, he finds work hard to come by. His greatest success comes as straight man in a phony vaudeville mind-reading act with the tipsy Madame Zulieka. While on tour in Omaha he meets acrobat Irene Fellara, and they have a brief romance. Twenty years later while Harry is on tour in Europe with a troupe of leggy blonde dancers, his train is stopped at the Swiss border and he finds himself stranded in the Alps in anticipation of World War II hostilities. Harry and his chorines take refuge in an Alpine hotel with a group of disparate travelers who are also marooned there. Among them are an American pacifist, British newlyweds, a cancer researcher, a German munitions manufacturer, and a beautiful blonde expatriate Russian aristocrat who looks suspiciously like the Irene of two decades earlier.
Mr. and Mrs. Smith (1941)
New York sophisticates David Smith and Ann Smith née Krausheimer have been lovingly and passionately married for three years, or so they believed. They are told individually that due to a technicality - an unresolved municipal and state jurisdictional issue at the time of their supposed marriage - their wedding was not legal, and as such they are not really married. Despite David saying earlier in the day that if he had to do his life all over again that he would not have married her (even though he loves her), it is Ann that decides not to marry David this second time around due to an action, or in reality inaction, by David in reaction to the news of their marriage being invalid. While Ann goes about her life as a supposedly single woman (which includes calling herself Ann Krausheimer), David does whatever he can to win Ann back. But winning Ann's hand may be difficult as part of Ann's new life is dating other men. One of those other men and the most serious is David's best friend ...
Snowed Under (1936)
Alan Tanner's new play opens in a week, but Tanner just can't finish the third act. He's retreated to a snowbound cottage to work, but blonde neighbor Pat Quinn wants to play. Producer Arthur Layton sends Alice, Alan's first wife, to help him stick to business. But then Daisy, his second wife, shows up wanting her alimony. Stranded with two wives, a girlfriend, and a jug of applejack, Alan still has to finish his play!
Swing Time (1936)
Lucky is tricked into missing his wedding to Margaret by the other members of Pop's magic and dance act, and has to make $25000 to be allowed to marry her. He and Pop go to New York where they run into Penny, a dancing instructor. She and Lucky form a successful dance partnership, but romance is blighted (till the end of the film at least!) by his old attachment to Margaret and hers for Ricardo, the band leader who won't play for them to dance together.
Private Lives (1931) - This one also sounds like it could be the one you are thinking of.
Elyot and Sibyl are being married in a big church ceremony. Amanda and Victor are being married by a French Justice of the Peace. Both couples go to a hotel on the same day and are put in adjoining rooms with adjoining terraces. Things go fine until Amanda sees her former husband Elyot on the adjacent terrace. While they both pretend to be happy, both make plans to leave, but their spouses do not want to leave as it is their respective honeymoons. So the other spouses each go down to the bar. This leaves Elyot and Amanda together and they reminisce. Before long, the sparks again fly and they both decide to leave together to the Mountains of Switzerland. They love, they bicker, they fight, they stop. Then it begins over and over. Then Victor and Sibyl show up at their chalet.
Separate Tables (1958)
It's the off-season at the lonely Beauregard Hotel in Bournemoth, and only the long-term tenants are still in residence. Life at the Beauregard is stirred up, however, when the beautiful Ann Shankland arrives to see her alcoholic ex-husband, John Malcolm, who is secretly engaged to Pat Cooper, the woman who runs the hotel. Meanwhile, snobbish Mrs Railton-Bell discovers that the kindly if rather doddering Major **** is not what he appears to be. The news is particularly shocking for her frail daughter, Sibyl, who is secretly in love with the Major.
Serendipity (2001) - more of a modern Hallmark "movie of the week" than a classic film, but somehow it manages to fit right in.
Jonathan Trager and Sara Thomas met while shopping for gloves in New York. Though buying for their respective lovers, the magic was right and a night of Christmas shopping turned into romance. Jon wanted to explore things further but Sara wasn't sure their love was meant to be. They decided to test fate by splitting up and seeing if destiny brought them back together... Many years later, having lost each other that night, both are engaged to be married. Still, neither can shake the need to give fate one last chance to reunite them. Jon enlists the help of his best man to track down the girl he can't forget starting at the store where they met. Sara asks her new age musician fiance for a break before the wedding and, with her best friend in tow, flies from California to New York hoping destiny will bring her soulmate back. Near-misses and classic Shakespearean confusion bring the two close to meeting a number of times but fate will have the final word on whether it was meant to be.