There are groups that will do estate sales to include handling the entire thing from preparing the items for sale to actually working the sale. I’m not familiar with the details but that maybe an option in which it may limit your having to be really involved.
Good luck as you move forward.
My suggestion would be to arrange “Mom’s “living area to be as seperate and private from the whole house, so you and she have privacy. If her room, or even if she could have an extra bedroom as a sitting room with TV, radio, a window to look out of and a sofa to lay down on..that would help a lot.
Then I would make sure she has enough of her possessions to “decorate” her new digs with you. Be sure to make her a part of this decision process. Even a few pieces of her favorie furniture would help her feel “at home>’”. It also encourages the “seperateness” that will help all of you to have boundaries..very helpful with two or more adults sharing a home.
Also, be sensitive to your wife’s feelings at this time. She may have some reactions which “don’t make rational sense” to you about what to sell or how...but remember, that home was part of her life, even if you all just “visited.” If you need to bring some stuff to a storage area, it is well worth it. Sometimes it takes a longer time to “let go of things. This will make you the true Prince you are. You will receive soooo many blessings from this.