The Guardian - Sherrilyn Kenyon
In the end, this reminded me of the Doctor Who episode when Rory is erased from Amy's mind after he's swallowed up by the crack in time only to come back as a Centurian a few episodes later where she remembers him and remember how she feels about him and all they've been through together.

As much as I like reading Kenyon's Dark Hunter/Were Hunter/Dream Hunters, this has gone on far longer than it should because I don't remember half of the characters and what they did before. Who is Ambrose and what deal did he make with Solin?