To me it'd have been more fun if Aria had already been a secret lover of Chiyo; especially if Ichiko then found out later.
[telenovela intensifies]
That's an interesting take. But then, it does sound like a telenovela.
I actually appreciate the realness of Chiyo's situation. The accusation of her "friends" that Chiyo did not care about her best friend whom she was in love with seemed like rubbing salt to the wound. And that montage of Chiyo getting married to a husband and having a "normal" life, at least for me, shows that Chiyo was not happy by default. She CHOSE to be happy every now and then within the one short life she lived despite the pain of not having a family with her best friend, or not ending with Aria.
"She was smiling.". I teared up a little when Aria confirmed this with Ichika if Chiyo had been really happy. Couple that with the fact that Chiyo advised her granddaughter (and possibly her daughter before that) to follow her heart's desire makes me think that Chiyo strove hard to live life without regrets but then had fallen short due to circumstances she could not control.