My ex hasnt come to get his stuff

On November 13th my boyfriend of two years ended our relationship and I didn't see it coming. While he cried during the break up, he said the reason was is that we are on two different time lines for marriage and kids (he's 31 and im 35). Anyway, we have now gone 25 days without talking and he, nor anyone in his family have reached out to get his stuff and my hall closet is full. Just clothes I have: 32 shirts, 5 hoodies, 4 hats, 2 pairs of jeans, 3 pairs of sweats ect. Also a guitar, two xboxes, a pillow, shaker bottles ect. This is not normal for me in a break up. If an ex and I have had to exchange things it's been a week or two.

I spoke to his sister (who he lives with) Saturday night and she offered to do the exchange for my things. I told her talk to my ex and see what he wants to do - nothing back.

Why hasn't my ex tried to get anything back?