At least Lillia was a child of love that way... The train wreck was obviously just the way to erase Wil's persona. Like he said, Wilhelm Schultz had to cease to exist.
Besides, wasn't Major Travas actually Wil? That's why I said it was quite a circle... In fact somehow in a romantic story like this it's hard to believe Allison would be seeing another man while Wil was still in reality alive even if not technically.