Man I've been working off and on this one for a bit. Inspired by a song I've been super into.
So The story I came up with is that Inkeri was separated from Volta during a food raid. She was bitten, and instead of trying to return to find Volta, she distracted the zombies as self sacrifice knowing she's already doomed. She pictures his smile as it comforts her in her decision knowing her last moments draw near.