Is there a way to preserve a corsage?

I saved my corsage from prom this year (my junior prom) because it was beautiful and it made me happy to look at it. I put it on the top shelf in the fridge, and it stayed fresh. I've been having a bad day today, so I went to the fridge to find my corsage. (The reason it makes me so happy is because my boyfriend gave it to me, and prom night was one of the best nights of my life.) Apparently, my grandmother thought it was no good and threw it out, because it wasn't there today, and my father hasn't touched it. My boyfriend will be going to my senior prom with me next year, and I know I'll want to save the corsage again. Is there a way I can preserve it, other than keeping it in a fridge, so that I can keep it without someone thinking it can be thrown out?