There is a book called Stuff: Compulsive Hoarding and The Meaning of Things. Might be worth reading in order to understand the mentality behind this.
There are professional organizers who specialize in hoarding. Not every organizer has had any training with hoarders so you need to look around for someone with the experience and training to help. Explain the situation, maybe pay them for an hour to discuss this, maybe show them the house and see if they can help in any way. They should at least have some ideas for you on how to go about this.
Personally I would be tempted to rent a storage facility in her name, hire some movers, and move every bit of it into the storage. Then clean the house and move in. But honestly I think your real problem is your DH. This is his mother and he needs to deal with her. If you and he are not on the same page you could be looking at years of conflict over this. Not to mention moving into this house full of stuff.
There are professional organizers who specialize in hoarding. Not every organizer has had any training with hoarders so you need to look around for someone with the experience and training to help. Explain the situation, maybe pay them for an hour to discuss this, maybe show them the house and see if they can help in any way. They should at least have some ideas for you on how to go about this.
Personally I would be tempted to rent a storage facility in her name, hire some movers, and move every bit of it into the storage. Then clean the house and move in. But honestly I think your real problem is your DH. This is his mother and he needs to deal with her. If you and he are not on the same page you could be looking at years of conflict over this. Not to mention moving into this house full of stuff.






Awesome! Now THAT is the type of good news I like to hear. Congratulations on a good job done well. 



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