I was first introduced to the concept of the ex-boyfriend (or girlfriend) box by the one and only Lorelai Gilmore. She advised her daughter Rory to throw all the mementos from her just-ended relationship into a box. That way, Rory wouldn't have to look at them, but someday, when she was old and grey, she could go through all her old boyfriend boxes and think, "My, what an interesting life I've had." Does that work in real-life, or just in Stars Hollow?
The first part of the Ex-Boyfriend/Girlfriend Box concept (can I just shorten that to Ex-Box?) is great. When you're in shock and pain, the last thing you want around are photos of your ex, gifts from them, prized possessions you acquired together, and other beloved but now-painful reminders of your past relationship. Get them out of my sight, NOW. But in such a fragile state, you might not want to be throwing/giving things away. You might accidentally toss a picture of the two of you, not realizing that your darling grandma is also in the photo, one of the few photos you have of her. You might be tempted to donate a treasured trinket to the thrift store, forgetting that your mom gave it to the two of you and in 30 years, you'll probably dearly wish you still had it. By stowing everything safely in a dedicated box, you can clean and exorcise your home, without making decisions you might later deeply regret. I highly recommend it.
But then what? When time has gone by, and your heart has healed (or mostly-healed), and you're happy again, it may still be difficult to go through your Ex-Box. When you're feeling strong, drag the box from the back of the closet (that's where Lorelai keeps theirs), and go through it systematically, if you're able. (If you still just want to get rid of it all, I won't judge.) Some of the items will, by now, have firmly moved into Give/Throw Away territory. Some things that you found too painful to look at might now be neutral- ah, a favorite book to put back on the shelf! As for the more-complicated others....that's where I just don't know. Do you get rid of all the photos of you with your former love, all your old treasures, out of respect for your new love (or your new life)? Do you consult your new partner on what he/she feels most comfortable with? Or do you simply keep everything, so that when you're old and grey, they can help you remember who you were, so long ago?