More than 200 million widows live in poverty worldwide, many of them falling victim to abuse - rape, prostitution and eviction all common problems. Others are simply abandoned to a life of social isolation because of their lowly status within society.
Yet their plight is often invisible, with many people unaware of the injustices taking place.
To highlight the inequalities involved, International Widows' Day (June 23) was introduced in 2005 by the Loomba Foundation, a UK-founded organisation set up to promote the welfare and economic empowerment of disadvantaged widows and their children, and was officially recognised at a New York-based conference at the UN in 2011. As UN Secretary General Ban Ki-Moon said, "No woman should lose her rights when she loses her husband."
Some 40 million of the world's widows live in India and life for these women is particularly hard. Not only have they lost their husband, but then society turns on them, casting them out as worthless, undesirable and invisible. In this patriarchal society it is still believed a woman needs a man to look after her - be it father, husband or son. And traditionally, when the husband dies, the widow he leaves behind is expected to forsake all pleasures, including wearing jewellery which often has sacred and status value.
While eight per cent of women in India are widows, only 2.5 per cent of men are widowers, due to the fact that men usually remarry. Widows, who can sometimes be as young as teenagers, cannot remarry and are seen as a financial drain on their families. Some mothers have even been cast out by their own children and forced to live on the streets in abject poverty.
For women who work on the land, often theirs by marriage, once widowed their plots are often seized by in-laws or their sons, leaving them without a means to earn a wage, and consequently without enough food to eat. Some women have also been accused of being witches to further ostracise them from society, then killed. Widows, especially those living in rural communities, who find themselves landless are frequently unskilled and are unable to get a well-paid job.
And although there are government benefit schemes in place to help widows financially, many are not aware of their entitlements.
Sushama Manglick, 40, from a small rural village in Jharkhand, eastern India, was widowed in May 2013 after her husband-of-14-years was killed in a car accident. A teacher, her husband provided for her and their two children while she stayed at home. When he died she no longer had a means to earn a living, could no longer buy enough food or pay the children's school fees, and almost immediately her relationships with both her family and his changed.
Her in-laws blamed her for his death and publicly denounced her, taking both her home and land as they were in her husband's name, forcing her to go back to her own family.
Sushama first stayed with her younger brother, but his wife accused her of witchcraft, claiming she was a husband-killer. She was consequently sent to an older brother's house, but again, Sushama was treated badly by her sister-in-law, and she and her children were treated as servants.
Last October, Sushama discovered Ekal Nari Sashakti Sangathan (ENSS), a group campaigning for the rights of widows - The Single Women's Campaign - which has helped her stand up for her rights and fight the prejudice she's encountered.
Christian Aid's local partner organisation Samuel Hahnemann Associates and Research Centre (SHARC) supports ENSS in Jharkhand, where 85 per cent of single women they work with are widowed. They're working with the government along with the National Forum for the Rights of Single Women to improve the lives of these marginalised women.
Women are encouraged to take the lead within their communities to have a stronger voice in economic and social affairs, widows are helped gain access to the financial rewards they're entitled to, and supported in finding jobs so they're able to pay their own way and better their lives. Some of these female leaders have also started to support large numbers of single women to identify the problems facing them in everyday life and find solutions.
Thanks to the support of ENSS, Sushama knows about the government benefits she's entitled to and understands her rights. Her children have been enrolled in a new school, she no longer feels helpless, but dignified, and works as a community leader to encourage fellow widows to fight for their rights. Although life as a widow is hard, she has no choice but to continue living under her brother's roof, Sushama now has the confidence to fight for her rights and those of single women, because she knows they're part of society and should not be excluded.