It was never going to be the most perfect political marriage.

Now, with less than four months until the state election, Cory Bernardi’s only Victorian MP has officially deserted him, accusing the federal senator of undermining her campaign and gossiping to journalists about her.

One year after she defected from the Democratic Labour Party to join Senator Bernardi’s Australian Conservatives, state crossbencher Rachel Carling-Jenkins has announced she will quit and potentially stand as an independent at the November 24 poll.

In a scathing resignation letter obtained by The Sunday Age, Dr Carling-Jenkins hit out at Senator Bernardi, saying he had failed to advance the party in Victoria, had denied her requests for a campaign budget, and refused to give her a say in the party’s decision-making.

“I know this resignation comes as no surprise to you — you have told numerous people, including reporters, that you have expected this,” she wrote.