I've been dating a widower for more than a year now.
Welcome to the board. It does sound like he may not be entirely over his late wife yet. Not that he somehow thinks that she will come back, but that keeping her things may feel like it keeps a piece of her with him. I understand the desire to do that but I think that after 3 years it is time to have let go of the physical reminders and the anger that she died so young and robbed them of their later years together.