Could be better, but the story is still told well.
The animation wasn't impressive. I like the doodle-drawing style of the art, but I feel like if it was cleaned up and the animation was both smoother and more consistent, it would help the feel of the Flash. The presentation also could have been improved; if pauses were used a little more carefully and more thought was put into the art to match the mood of the movie itself, the mood may have been enhanced.
But I still think that overall you did a fine job using grayscale and symbolism to tell a sweet, simple, innocent, nonviolent story of loss and love without any words at all. It didn't feel forced or totally unnatural, which is more than I can say about most other love stories I've seen.