I want to share a beautiful thought I heard several years ago, which has given me Chizuk often, especilly considering the circumstances that it was said:
The levaya was for a wonderful Neshama, a teen who died after a car accident. Her teenage brother spoke at the heartrending levaya, and he took a few moments to address the kahal. He thanked everyone for all their Tefillos, Kabalos, help and support over the few days she was in a coma, then said: Don’t think for one minute that ANY of it was wasted! Hashem heard every word, collected every Mitzvah, every thought. Although we didn’t get the answer we had hoped for, you can be sure those Tefillos and Mitzvos will be stored in Shamayim and help someone else. (this is how I remember it)
This was such a nechama then, especially as it was said by her tear-choked brother.
May it help you as well, and may we see the coming of Mashiach very very soon.