"I was very frustrated because my husband feels he can't take a full 3 weeks off work for our upcoming transatlantic cruise and we only have 2 nights/3 days in Barcelona."
i had the EXACT same issue--and so i'm staying for a week and a half after my husband leaves. i figure we're spending enough time and money just getting across the ocean, i might as well make the best of it! staying without him sounded like a crazy option in my head when i first thought about it (he leaves paris on the eurostar to fly out of london the next day--i fly to barcelona for a week, to london for two additional days, and then home), but now i'm almost more excited about the alone portion of my trip than i am about the 'us' portion!