I believe for chapter 37 next month, Sayaka is going to confess to Touko. But, eventhough Touko already become "herself", I strongly believe she will reject Sayaka's confession. Maybe that time, Sayaka also will get to know what happened between Touko and Yuu probably she will shock as well if she know Touko has already kissed Yuu many times, LOL.
At that point, Touko will realize what happened around her life after a few days she won't see the appearance of Yuu, especially in that school trip to Kyoto and maybe find a solution about her feelings and what she will gonna think about what she feel of Yuu.
Well, many Yuri stories are more likely have the 1 or 2 main characters have a complicated and twisted personalities that make it interesting to read.