Memory and Identity are such complex things. Who can tell when one ends and the other begins? Speculative futurefic. Very speculative
So much of fanfic (and the series itself) are of other Ritsuka, and yet if the first returns he ends up in much the same situation of a life he can't remember. I love the way you explored the differences from the gap and the glimmers of the other Ritsuka and kept hints of his mother's problems despite the fact he's back to being 'her' Ritsuka. And the ending is just perfect.