ANC MP Makhosi Khoza says there is little cause for celebration following the failed motion of no confidence in President Jacob Zuma via secret ballot.
The majority of ANC MPs "unfortunately chose to endorse the steady and relentless destruction of the ANC", she said in a statement on Monday.
"In those voting booths, we were all confronted with the same choice, to choose between right and wrong. To choose between self-enrichment and the service of our people," the outspoken MP said.
"The majority chose to continue the reign of a kleptocracy that has brought our once mighty and revered ANC to its knees."
She reckoned the ANC had become a shadow of its former self and had sided with a president who "failed to uphold, defend and respect the Constitution".
Khoza praised National Assembly Speaker Baleka Mbete for having shown fortitude in agreeing to a secret ballot.
"Even those who abstained from the vote offered us a glimmer of hope of the moral conscience that does exist within ANC branches and thousands of rank and file ANC members."
A total of 198 MPs opposed the motion and 177 voted for it, after it was debated in the National Assembly last Tuesday. There were nine abstentions.
Khoza questioned why women in the party appeared to receive harsher treatment than men.
"I am accused of extreme ill-discipline and the condemnation of me by the party was swift and unequivocal. No time was wasted in charging me, but interestingly, men whom have similarly criticised the leader of our party remain untouched."
She said Deputy Higher Education Minister Mduduzi Manana had still not been suspended, nor had the party initiated disciplinary action against him. This was despite the fact that he had admitted to assaulting two women at the Cubana nightclub in Fourways, Johannesburg, last weekend.
Khoza said the ANC's application of disciplinary action was not just inconsistent, but appeared to be largely informed by how badly one had annoyed those in power.
"Action is taken decidedly quicker if you're a woman, except of course if you're the woman on the receiving end of the beating."
She described as "astonishingly callous" ANC Women's League president Bathabile Dlamini's comments that there were senior government officials worse than Manana.
"These are the kinds of things that have weakened and continue to weaken our movement. We are not weakened by me speaking out against corruption and patronage.
"We are weakened when our leaders choose to shut down their critics. We are weakened when currying favour becomes our currency and when those who break the law are literally given back doors and gentler treatment to spare egos."
The only "foreign power" weakening and influencing the party was the Gupta family.
"A lethal combination of corruption and state capture has a stranglehold on this country and that will not change until this government chooses to actively root out those propping up, and benefitting from, state capture."
Khoza said it was clear that the only ones being disloyal to the ANC were those abandoning the people who had elected the party into power. She said she was grateful for the "enormous support" she had received from many South Africans.
"They gave us their votes, it's our duty to fulfil our promises and to channel every cent of government funding to better the lives of all our people, not just a powerful few."