My ex has been promising me for a while that he changed his address, but hasn't because I keep getting his letters. He would randomly stop by to pick them up and I'd remind him again, and he would say that he had done it already. I think he's avoiding it as an excuse to keep seeing me and talking to me like garbage.
I have a stack of his letters and I told him I'm done with it and he needs to collect them. Some of these are over a month old now. I set them aside safely and haven't touched them. He flaked and didn't pick them up again because I said no more.
What do I do at this point? I don't want to do anything that violates anything USPS, and i don't know if I can write 'Return to sender' on all of these. I just want to stop receiving his things.
EDIT: oh my gosh I did not expect this many responses. Thank you all so much for your help. I'm just going to return the bundle of them in my mailbox and write " not at this address" as was suggested. Living with him for so many years has given me a great deal of anxiety over minor things and i'm working to overcome that. Thank you all for your help and support ❤️