In his political memoir, he has described being “hurt” after a party heave to remove him as leader last year, adding that party members “pulled the trigger” too fast.
The publication and revelations come as his successor, Joan Burton, battles to regain lost support for Labour ahead of what will be a testing general election for the embattled party.
Speaking to RTÉ yesterday about his book, Mr Gilmore set out how Labour had twice contemplated walking out of the Coalition over controversies. He spoke about tense talks between Fine Gael and Labour before the budget in 2012, where there were divisions over tax changes and cuts.
Labour wanted increases in USC for those earning above €100,000, while Fine Gael, in lieu, wanted to cut welfare payments for the unemployed.
“We had a meeting of the Labour ministers about how we were going to approach this and we had a number of options, one was to collapse the scrum,” said Mr Gilmore.
What was eventually agreed for the budget was a package of measures of ‘wealth taxes’, including increases in capital gains taxes and higher taxes on large pensions, he said.
The second issue where Mr Gilmore said the Government could have collapsed centred on the resignation of the former garda commissioner Martin Callinan, as well as the revelation that phone calls had been recorded in garda stations for years.
He said he met Taoiseach Enda Kenny the morning before Cabinet on Tuesday, March 25, and was annoyed at not being informed of revelations of the recordings, which his Coalition partner had known about since the previous Sunday.
However, a later revelation that Mr Callinan had in fact informed officials through an undisclosed letter, weeks earlier, of the secret recordings caused even more tensions.
“If it had transpired that the Taoiseach or the minister for justice had known about that letter before the cabinet meeting and had not told me about it, then that would have been the end of the Government,” he said.
Mr Gilmore said it had been “a bit of fun” during the 2011 election campaign to campaign for him to be Taoiseach, an idea suggested by Labour Youth.
In his memoir, it is also revealed that Mr Burton was “hugely unhappy” when, during negotiations for Government with Fine Gael in 2011, she was told she was getting the department of social protection. Mr Gilmore said she had wanted foreign affairs.
Mr Gilmore admitted that controversies around Irish Water, including the revelation that €90m was spent on payments to consultants, contributed hugely to Labour’s misfortunes.
He was later “devastated” by the bruising 2014 local election results for Labour and recognised the need to resign after he lost the support of the party’s centre.
He said he was “hurt” when party figures moved to oust him and said they “fired the trigger” too fast.
“It was a case of being marched down the corridor and being dismissed,” he later said.
The revelations in Mr Gilmore’s memoir come at a tough time for Labour, on the back of mixed poll results which indicate little if no returned support since the budget last month.