Even though it's already been said in many different ways:
Yuu's and Touko's relationship isn't for the faint of heart. And at the same time, they make each other incredibly happy. While Yuu intentionally helped Touko grow, Touko unintentionally helped Yuu grow. That's the kind of relationship that makes it.
Personally, I think Sayaka still has Touko on a pedestal. She's saying she loves her no matter what, even after seeing all of her sides. But I don't think Sayaka has seen all of Touko's sides. I think she's just now beginning to see what type of person Touko truly is, but she's pushed this love of hers for so long, that she's afraid to back out of the hand and instead pushes all in.
Sayaka is projecting. Touko is still confused. And Yuu is just suffering.
Until Sayaka can come to terms with her past, she'll never really be able to move on. Sayaka is in need of her own personal growth. And while I commend her for confessing, and she is making attempts at being honest with herself, I think she needs a deeper self reflection as to what she truly wants and desires.