Colleagues and others who worked closely with Ms Nimmo have been left devastated.
She was described as a "heroine" in one tribute posted online by anti-family violence advocates.
"You stood for and championed so many causes - so dedicated, driven and determined to make our world a better place. You gave all the energy and expertise that you had to help others. A true leader, your work ethic and practice was inspirational but you also conducted yourself with such warmth and care and a bright smile for those around you," wrote Kristin Dunne and Lesley Elliott, trustees of the Sophie Elliott Foundation which aims to prevent violence against women by raising awareness about the signs of abuse in dating relationships.
"New Zealand has lost an incredible woman but heaven has gained a beautiful angel. Give our love to Sophie."
Sophie Elliott was murdered by her former boyfriend Clayton Weatherston who is serving a minimum 18 years of a life sentence.
Deputy Commissioner Glenn Dunbier said police are deeply saddened at the sudden death of Ms Nimmo, who was awarded the Minister's Prize for topping her graduation wing.
"After spending the early part of her police career as a legal adviser, Brigitte focused on family violence and victim liaison roles where she was a passionate advocate for the vulnerable in our communities," he said.
"Brigitte had a sense of energy and professionalism which was an inspiration to everyone."
Her family said they were very proud of Ms Nimmo's career, particularly her involvement in setting up the family liaison response in the aftermath of the Pike River mine disaster.
"This was an incredibly trying time which saw her dealing with a tragedy which had not led to that many victims, and people affected, since the Mt Erebus disaster," according to a family statement.
The experience which Brigitte gained from Pike River led to her involvement in the Canterbury earthquake in February 2011 and other key accomplishments included her secondment to the role of National Family Violence Co-ordinator, where she led several important pieces of work like the introduction of Police Safety Orders.
A service to celebrate Ms Nimmo's life will be held today but her family have asked media to not attend.