It's up to you what you decide to do with his stuff. Personally, I would send it back and be done with it. I don't like people to know when I am bitter or hurt -- I feel like I will be giving them satisfaction in knowing they hurt me. I usually just act as though I am indifferent and try to get on with my life. When my first boyfriend cheated on me and broke my heart, I seriously made a huge scene in front of lots of our friends, I burned his things and letters he wrote to me and was very dramatic about it all, but I only felt embarrassed later on. After that, I would just give an ex his things back, wish him luck, and tell him maybe we can be friends later on yet never call him or try to contact him in any way. You might find he calls you and says he was wrong (which always feels like retribution) then you can just say "sorry, i've moved on. but good luck!" I would think destroying his things would only show him how hurt you really are, and that he would get some sort of satisfaction in knowing how much you care, which he defintely doesn't deserve. Convince yourself you are too good for him anyway and hold your head up high!!