Whatever you choose to do with stuff that belonged to an ex is valid, however, it is important to text them or give them a call to know know if they’d be coming to pick up their stuff or they’d want you to “take care” of them. If they want their stuff back, be mindful that you two are not together anymore and that this necessitates a change in both of your behaviour toward one another. It would be best to go through a third party, but an amicable public meeting would also be appropriate. It may bring up emotions and that would be natural. Have a plan to deal with your own emotions and do not take ownership of theirs. If they do not want their stuff back, and you probably are not ready to toss them all away (very understandable, as they are items of someone you once had good time with), you may stuff them all in a box and label “do not open”, then you proceed to hide the box somewhere out of sight. Another thing you can do is trash all the items, by doing this, you are burying every tiny thing that may attach you to such ex. Either ways, your peace of mind is what matters, and how best you are able to move on with your life. Wishing you all the best, irrespective of the action you take.