you could decompile your swf and hope for the best. at least, you would be able to extract resources from your project.
and you now know what every programmer knows: save your project files frequently AND save with different version names like yourproject_01.xfl, yourproject_02.xfl etc.
Thanks for the reply.
This is exactly what I ended up doing. I used a program to decompile the swf into a fla file. It wasn't perfect, but at least I didn't have to start from scratch. All of my graphics were there. I just had to adjust the layers and add my ActionScript back in.
I had been saving every few changes, but I didn't save it with different version names. I've definitely learned my lesson!