Renu has been blinded by the attack
A day in February 2006 is imprinted as vividly on Renu's mind as her body.
In the quiet, narrow lane outside her east Delhi home, she had been bathing the family buffaloes when her father's tenant, a mug in hand, came towards her.
She thought he wanted water but he greeted her instead with threats and a shower of acid.
Her sister Rajni, who came rushing out when she heard the screams, remembers how Renu's "clothes were melting off her body as though they were plastic".
The acid attack was so lethal that it killed the half-bathed buffaloes and has left Renu blind and disfigured for the rest of her life.
In an ironic role reversal, Renu who had been the mother to her four younger brothers and sisters since their mother died 11 years ago, has now become entirely dependent on them.
In Bangladesh, Pakistan and India, the number of acid attacks have been rising - and there are some facts now beyond dispute.
The largest numbers of victims come from the poorest backgrounds and are women who have rejected their husbands, employers or would-be boyfriends.
The attack is not committed in a fit of anger or "passion" as is popularly believed but is premeditated and intended to kill or maim.
Acid attacks on women are a problem in South Asia
The attacker's message in no uncertain terms is that if you can't be mine, you won't be any one else's either.
Mamata's story goes back 12 years, to when she was 14.
Her crime was that she refused to stay with a husband who had decided to marry again.
Over several months, while she stayed with her parents, he coaxed, threatened and tried to persuade her, but to no avail.
One day catching up with her as she headed for work, he suggested she come and sit for a while in the quiet, secluded park en route.
Then as she made to leave he grabbed her hands and threw acid over her face and arms, leaving her permanently scarred.
Twelve years on, she tries to live as normal a life as she can, though in a society where looks are everything, especially for women, getting a job, even as a domestic help, can be difficult.
One school teacher, scarred by acid, had to quit her job because the children found her frightening.
Most employers will not accept acid victims back, punishing them for a crime committed by someone else.
The National Commission of Women has of late begun to look into the possibility of a medical scheme for acid victims.
The numerous surgeries and skin grafts take decades to do and cost several thousand pounds which the victims are mostly unable to afford.
Renu's family, for instance, was hardly poor but the medical and legal fees have reduced them to just that.
Mamata was attacked by her husband when she spurned him
Cases of acid attack are regularly reported in the newspapers, but the government institutions and even NGOs are only just beginning to wake-up to the issue.
So as yet there are no countrywide figures for acid victims, let alone insurance or rehabilitation schemes for them.
However, a pressure group, the Campaign and Struggle Against Acid Attacks (CSAAAW), has been launched in the southern Indian state of Karnataka to increase awareness.
The group has put together a list of more than 56 victims in the state alone.
And while some might see this as evidence that it is just a Karnataka issue, the growing numbers reported by the media point to the fact that too many others are silent victims all over the country.
For many like Mamata, injustice continues in the courts - her husband is still out on bail, the father of two children, while she has nothing but her scars.
All too often cases are seen as non-criminal offences and the offenders are let off with a lighter sentence.
Many offenders seek bail and delay cases for decades.
According to Anubha Rastogi of the Human Rights Network, which has joined hands with the Karnataka Campaign, stiffer punishments and a change in mind-set even with the legal fraternity are urgent needs.
"Where a case of acid attacks is being heard and the judge turns around and says - if she had agreed to him [the attacker's request] this would not have happened - I do not expect any justice."
The group is also demanding a ban on sale of acid at shops.
But some say the real problem lies somewhere else.
When will men in Indian society begin to accept that women are individuals with rights and choices, they ask?
Until that happens, Mamata can only pray for justice from the Indian legal system. Or Renu, whose attacker has been given a life sentence, can continue to demand an eye for an eye.
But the truth remains that women are horribly vulnerable.