Shortly after my divorce from XAH was final, I threw out a box of mementos/photos. My thought process was "that is all PAST. I am starting NEW. No need for this."
I've since wished I had just set it aside and looked through it when I'd had some time to settle down and was thinking more clearly. I met him when I was working as a bike messenger and I tossed all that stuff. In time since then, I've wished I kept that stuff--I mean, how many people get to be bike messengers? It was a very cool time in my life, but now i had trashed all my physical reminders of it, even though I'd worked the job for 3 years before he came on the scene.
So my opinion would be to save it but set it aside, make the final decision later.