I don "t know if this is the answer you "re looking for.
4 years before present day, mc "s aunt has a disease that if left untreated she will die, but the treatment is very expensive. Meanwhile Aria and mc are together, mc "s personality changes, he becomes addicted to alcohol, he has a hard time finding the money he needs... Aria says this is not the man I fell in love with and tries to help mc, but mc won "t let her and becomes more and more distant from Aria. Aria breaks up with mc because Aria can't stand to see mc like this anymore and believes that maybe her breakup will bring mc back to himself.