Echoes,
I can understand, oh so much, how hard it is. I hate those things! To me, it's like asking me to pretend I'm perfect when I know I'm not. I tend to forget that no one is!! You've proven on PC many times how valuable you are. Try to give yourself permission to take the risk and put you on paper, it's all transferable!
I like the idea of responding as if to your former manager, the review is for the whole year, isn't it? I also agree with Pachy, the words you used above sound like excellent accomplishments to me. If you're honest with the depth of your being, you will find you have accomplished much.
You can do this!