"She was leaving the party that weekend until the beautiful man came."
Translation:Hun var ved at forlade festen den weekend indtil den smukke mand kom.
"Until" is the wrong preposition in English. The word is "when". And she can't be leaving the party for hours or days, as the progressive (plus "that weekend") here suggests in the context of the sentence. "Weekend" is in the wrong place. There are too many things that are wrong with this sentence.