I'm not sure if it's how this is supposed to be taken, but I like how it's not enough. The words of Sunny's friends. What Basil says to him before Memory Lane, the good memories you see on Memory Lane, the encouraging words of his friends, and what the versions of them at the music stage say.
He cherishes those words in the fight against Omori. They're words that give him strength to keep going.
>KEL: Friends... Friends are supposed to be there for each other.
>AUBREY: I hope you can find some peace... or you know... some happiness.
>HERO: Last time... We made the mistake of leaving each other when we needed each other the most. This time... we'll stay together.
>BASIL: Maybe one day... things can go back to the way they were before.
>MARI: You'll forgive yourself... Won't you... SUNNY?
But it doesn't work. The forgiveness, the desire to keep living, can't come from them. It's just too unbelievable that they'd forgive him. Mari loved him and he killed her. Their friends loved Mari and he killed her. He loved her and he killed her. What Omori says is what Sunny believes, and that belief is stronger. He succumbs and loses. But even still, he can still decide to keep going. He can't overcome Omori. He can't forgive himself. But he can choose to live in spite of it. Tell his friends the truth even knowing he'll lose them. Final Duet is saying goodbye. Goodbye to Mari, goodbye to the good times, and maybe goodbye to his friends. Maybe the Basil in his dream was right and their friends can forgive them, and he'll hold on to that. But regardless of what happens, he's chosen to keep going. To accept the consequences of his actions and what he's done. He won't run away anymore, not into dreams or delusion.
I think.