Yuzu should break up with Mei. She just give her more without any reciprocate. My heart is breaks for Yuzu to see her suffering.
Mei had a week to do her f work, forgot her fiancée's birthday and not even try to change or be better for sake of Yuzu. Maybe a little bit... but It feels a truly one sided love.
Mei character is not improved, morover is worse than before, still an emotionally crippled person who would screw with anybody who is pushing her a little bit, like happened with Amemiya sensei. About Yuzu... Yuzu is an intresting toy for her which is recently discovered, do not know what to do with it, where to place it, so... when needed she takes out, when not, put back into the drawer.