Just finished playing your game! And I must say, I absolutely LOVED IT. I like the flow of your writing, there were a few grammar mistakes but they were seldom and in no way distracting.
Rest of my thoughts in spoilers;
I love the hope that this gave. A dying girl inspires a boy who wants to end it all to live. One thing I really liked about it is it brought up how isolation can be a killer. Not telling your feelings could make life worse when the fix is simple. While I've never been suicidal myself, I've suffered deep depression recently and wanted to give up... by give up, I meant throw away my passions and dreams and just sit and waste away doing nothing but binge watch music videos and sleep all day. But I knew this wasn't right. Keeping myself isolated made things worse and when I finally opened up about it with friends, they were so worried and gave me words of encouragement, some even know how I felt. So yes, being isolated isn't good, sometimes opening up is the answer too. You can't get help if you don't ask. I had a friend a few years back who was a member of my game dev team and most of the time I knew him, he was in the hospital. He even recorded a lot of his lines for me whilst in the hospital. The day came when he knew he was going to pass away, I remember that final day he not only told his feelings for me but also told me to keep writing and making VNs because "what you make is really good, you might help someone someday". Remembering the promise I made to him, I have to keep living life to the fullest. He meant a lot to me, so this VN had me bawling. While different from my story, it still had a lot of relateable elements for me that tugged at my heart strings and keep reminding and inspiring me never to give up, to live, to be happy, and to help others. I loved how at the end when 10 years later, he decides to have a chat with the kid that reminds him of himself, indicating that the spark of hope will be spread. It reminds me of an old VN I was working on, which is near finished and I should release someday lol.
Also. knowing the truth about the girl, it makes the bad ends even MORE heartbreaking because not only does it indicate our main gave up, but that girl's final wish was probably left unfulfilled.
But yeah, your story meant a lot to me. It was beautiful, so don't think your writing is terrible. Keep at it! You managed to make me literally cry and reminded me of why I love to do what I do, and why I need to keep at it.
Congrats on finishing NaNoRenO. It is a beast I have yet to defeat myself xD