Maya already knows that the MC loves her. He didn't tell Maya, but there was a heart emoji between the two. EP4, follow your heart.
The problem actually lies in the fact that you can only give your heart to one person. Therefore, there must be another way, and there is. The three hearts of Josy, Maya, and the MC must merge into one heart.
I'm just reporting what I read from DPC (Pink).
I don't think it's so that Lily is or was the MC's ex. I can very well imagine it's so that Lily was with a possible brother of the MC.
I'm not denying it's so that Josy loves the MC, but Josy doesn't say it's so that she doesn't love Maya anymore. She just doesn't know how she feels about Maya, and there are reasons for that. Maya has changed a lot, and Josy first needs to sort out her feelings for the changed Maya. Josy only knows the frightened Maya, and now Maya is free from her father and blossoming. Before, Maya was afraid of not being able to keep up, and now Josy has this fear. That's why it's so important for the MC to show Josy and say that he loves her.
It's basically the same as between Zoey and the MC. Both Zoey and the MC have changed. They haven't communicated with each other for a long time. Zoey realizes that she loves the MC, but she can't really keep up with the MC anymore.