Lol is this chapter two different years? The first part is Uta in college and then it seems like another time skip after she graduates and works.
In the first part it seems like she has moved on, but then goes back to living with Kaoru.
I guess all three of them still live as a family in the end again, with Reiichi living next to them.
Is Uta dating Kaoru now? Personally to me it feels like they're still in a "family relationship" and not romantic, and Uta is content with that. I think the author realized it would be hard to have them date after all the building around Kaoru not being interested in Uta this way. So an open ending was the closest to a "happy ending". This was a bit anti climactic, although I think we needed more chapters to make a proper Uta moving on ending too. Therefore the only ending the author could have pulled given the situation.
The story developed some deep themes about unrequited love, but in the last two chapters it was rushed and we couldn't even have a satisfying ending regarding the theme of moving on to begin with. The author didn't have the guts to go full everyone has moved on but this is just life ending.