Plum is a people focused dog and loves attention and being part of all you do in your day. She most likely has never been socialised with other dogs as she cannot read other canines' advances
to play and therefore becomes fearful. She may never really enjoy the company of other dogs but if she has a human companion who understands her fears and gives her the confidence to meet others of her kind hopefully she will become more comfortable.
Plum has had no training to date - another reason for her needing an experienced human companion who has worked in the past with large dogs and their issues