Yeah so everything was Hayato's fault, because he DID abandon him. That letter was just to say "yeah I'm not going to come, I swear I love you but I'll still get married. I swear it's for you and not because I am a coward who don't want to give up my lifestyle for you."
Touma would have killed himself anyway even if the letter had reached him, because Hayato never chose him.
Yeah so everything was Hayato's fault, because he DID abandon him. That letter was just to say "yeah I'm not going to come, I swear I love you but I'll still get married. I swear it's for you and not because I am a coward who don't want to give up my lifestyle for you."
Touma would have killed himself anyway even if the letter had reached him, because Hayato never chose him.