[TOMT][Manga] Looking for a Manga...

I've read it already, so I know a little about the plot - mostly the ending - but can't for the life of me remember what it's called.

If I remember correctly - Near the end, one of the main female characters (love interest??) dies... on, or just after a scene with a large boat/ship. And then the main character end up travelling on his own right at the end. It's left rather open-ended.

Possibly historical, or, at the very least - in a fantasy setting, with swords etc. Also may be a prequel to another series but I doubt that.

I'm sorry if this is really vague - It was quite a while ago I read it, at least 2 or so years ago, so I don't remember too much.

I'm completely drawing a blank so any help would be much appreciated.