/t/ - Theories

What if we are mistakenly confusing "end" with "goal"? And the cause with consequence.
Although the goal in the game is to collect all the effects, it doesn't say that Madotsuki has to die. By collecting all 24 effects, she (we) has the option to jump or not. She doesn't have to. She (we) has the option of not jumping and going back to dreaming (or to play NASU).
The ending doesn't mean everything happened to make her suicide. It simply shows the obvious consequence of jumping from a building. And, there, we must not confuse cause with consequence:
She doesn't die because the game ends. The game ends because she dies. While she lives, the game goes on. We are not forced to make her jump. We have the choice. And we have consequences to deal with.

It may sound sad and pessimistic to realize we can not "fix" her problems in order to allow her to leave the room and live a "normal" life. It makes us think that she'd rather die than leaving her room.
Maybe some people think this is a miserable life. But we enjoyed the time we spent with Madotsuki, even without leaving her room, and we feel sad with the idea of her death. Maybe we should get rid of our obsession on "fixing" things, and feel glad that Madotsuki can keep living in her closed room and her dreams (and NASU).