I forgot the name of a manga I read some years ago.

I'm not sure if I'm mixing up different storys.
This is what I remember:

It's a high-school love story. The girl is shy and doesn't follow her dream to make music. I think her late grandmother taught her. She tries to do what her parents want. It changes when she meets a boy, who has some problems in his home.
I think he lives separated from his family, because he has problems with his father. He encourages her in her dream. His hobby is either astronomy or photography, I think.
At the end of the story she plays the piano/orgel at the improvised wedding of eloped friends and her parents allow her to persure her musical education. Also her then boyfriend proposes in a church, where she has to find the heart-shaped ring on the walls, where he had projected a night sky.

I hope can help me with this.

Isn t that Kare First Love?

Yes, that's it. Thank you. I've searched a lot, but somehow it slipped through my radar.