Ed Miliband's wife has attacked her husband's "nasty" critics and warned them she is "up for this fight".
Justine Thornton told Labour activists that however brutal the attacks become on the party leader in the run-up to the general election, she will take them head-on.
But the personal onslaught faced by some politicians is likely to deter principled people from entering public life because the "price seems just too great", she said.
Justine Thornton said she was 'up for this fight' when her husband bids to become prime minister at next year's general election
The environmental lawyer has previously made clear her frustrations at being viewed as a "politician's wife", apparently quipping earlier this year that it was "not a role I applied for".
At last year's annual conference she won plaudits for her stylish appearance but told a fringe meeting she was ''more than a dress''.
Addressing party activists at a private meeting during this year's gathering in Manchester, she gave a glimpse into the impact the spotlight has on family life.
She said: "We are less than a year away from a general election. People are saying to me now, what's it going to be like for you over the next year? What's it going to be like for your family? How do I feel about some of the personal attacks on Ed?
"Well, the answer is that the way I see it, we are in a fight."
She added: "On a more personal level it seems to me it's about whether principles and decency count for something in public life.
"It's about Ed, and all the other politicians who try to do the right thing despite the personal attacks.
"And it's about all those principled, decent people who aren't in politics, who might think about coming into politics and then think they won't because the personal price seems just too great.
"So those are the reasons why I am up for this fight over the next eight months. However nasty, however personal, however brutal it gets over the next eight months, I am up for this fight."
Over the summer, Mr Miliband attempted to tackle his "geeky" image after being lampooned by cartoonists as Wallace from the Wallace and Gromit animated film series and ridiculed over his attempts to eat a bacon sandwich.
"I am not from central casting," he said. "You can find people who are more square-jawed, more chiselled, look less like Wallace.
"You could probably even find people who look better eating a bacon sandwich. If you want the politician from central casting, it's just not me, it's the other guy."