I am sorry for your loss. My mother was the opposite. When my father died she gave away his things and had my brothers take his old army uniforms right after he died. It would have been nice to have a few things. She had many losses in her life and was not sentimental in the way of needing the material possessions. We all process grief differently. It has only been 2 weeks, so give her some time and then perhaps talk about what is most important to her to keep. You may start looking at his things and be reminded of good memories. I do not think pain and grieving are bad, or to be avoided. Give yourself time as well, however long it takes, which is different for everyone. As you said, it is difficult because it is her house and you will probably move out eventually.
