I've been trying to find an anime movie that I watched about 20 years ago on TV. I don't remember the title, obviously, and I don't remember many details about it either. I think it was fantasy/science-fiction. There was a war going on. I remember spaceships, but also hot air balloons (or maybe zeppelins?). One of the main characters had a girlfriend back home (or maybe she was his sister? It was someone he loved and wanted to see again). I think her name might have been Juliet, but I could be wrong. At the end of the movie when the war ends and he comes back home she's dead, she's a ghost or spirit or something.
There was also a pair of lovers who were forbidden to be together, I think they were from rival kingdoms, and I *think* they were a prince and princess. They meet in the woods on this bridge, and it's supposed to be a secret meeting, but something bad happens, I think the bridge crumbles and they die.
I know this is all very vague, but if someone could help me find this I'd be so very grateful!