i get what people in the comments are saying, but i also have been at Kanna's place. i confessed to one of my girl friend, she rejected me, we agreed to keep being friend. might be weird for some people, but it wasn't for us.
I totally understand that.
My first love interest (and a real one) was unrequited, but she still became one of my best friend (that was 30 years ago).
From my point of view, true love is wanting someone to be happy. She married someone really nice, so I've always been happy for her.
And for fun fact, coinciding with Kanna's story, she had a love relationship (it was only the beginning and not sure it was real that much actually) but the one she is married to now still decided to confess. He knew she had someone, but he still wanted her to know. He did well cause he finally won her heart. And I think he was right.