Hi Talia and Welcome! I am somewhat familiar w/OCD. Your DH's first step is to acknowledge to himself that he does indeed have OCD. Contact the OCD foundation and they will send you some literature.
Maybe if he sees his sx's in print, he will see himself. My brother is a hand washer, which is one of the more common OCD sx's, along w/hoarding.
He knows he is doing these repetitive acts, but it's a total denial thing; and he really can't help it. He's probably as frustrated as you are...
One of my friend's DH's sx's include checking and double, and triple checking the locks on the doors and windows every night b4 bed. It's a ritual.
Try and understand that he has these compulsions and obsessions to hoard. Like I said, there is good info out there, plus members here who can help. take care and welcome again....

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