The group burst back on to the scene by invading BBC1's live National Lottery programme last weekend.
Six protesters, including O'Connor's partner Nadine Taylor, interrupted the programme on Saturday night. Presenter Eamonn Holmes was ushered off the set as they waved placards in protest against the family courts.
"After it was reported that we were involved in a plot to kidnap Leo Blair, I felt I had to disband the organisation," said O'Connor.
"But we still had a lot of good members on board, for whom Fathers 4 Justice was their only hope - so we decided to stage a comeback.
"By including a woman in the protest, we are sending out the signal that we are not just an organisation for fathers, but also for mothers and grandparents."
Although no longer leader of the revived organiation, O'Connor will continue to act as an adviser.
But Jack O'Sullivan, co-founder of Fathers Direct, sounded a note of warning. "High-profile tactics such as these tend to polarise opinion and mean you are less likely to be listened to," he said.