It was five years ago that Emma Cooper and her husband separated. Since then, her divorce has dominated her life. The 47-year-old has spent much time and energy fighting her ex in court – over custody of their three children and financial support – with legal bills topping £85,000.

Her former partner, a banker, dropped his maintenance payments to a bare minimum after being made redundant, despite having a six-figure payout and the strong likelihood of another job in the pipeline. Cooper is now hoping her case may see a change in the law, where redundancy payments can be taken into account as income in child support cases.

“When he left, his attitude was ‘and I’m taking my money with me’. He uses money to punish me. He pays late, he doesn’t pay the right amount, or doesn’t pay at all. He stays in control, and in my life, in a continuation of a very toxic relationship.”

Luckier than many women in the same position, Cooper lost the family home but has a house for herself and her children. “Not that it is an asset I can sell, as we need to live in it,” she said. “My pension is worth £18,000; his is £228,000.

“I know I’m luckier than most – most women I know got nothing, and had to get on with it. Anyone who had a partner who is self-employed is completely screwed. Women who gave up work or financial independence to raise children are just stuffed by divorce.”

Her view is perhaps skewed by her experience, but it does have the heavyweight backing of a new report by the Chartered Insurance Institute (CII), “Risk, exposure and resilience to risk in Britain today”. The research emphasises that divorce and separation are a significant financial risk to women left “vulnerable” by joint decisions made while they were in a long-term relationship. The average divorced woman has less than a third of the pension wealth of the average divorced man, while 10% more divorced women expect to rely on the state pension than men, 41% of whom have an occupational pension. To compound this issue, women are more likely to have more caring responsibilities, and to suffer mental health problems.

Barbara Reeves, a partner at Mishcon de Reya, has decades of experience in family law. She says risk is inevitable in divorce – and managing it is crucial. “There is a perception that women in England do well out of divorce – with London being described as the world’s divorce capital,” she said. “But it’s important to remember that if this is the case, it is only so for the wives of the super-wealthy. The reality for most women is that they have often created homes, raised children and supported their partners while their own careers have stood still, or progressed at a considerably slower rate.

“The money these women could have earned – and consequently their potential to save for their own future long-term needs, including retirement – has been significantly compromised.

“Divorce has always been a daunting prospect for the financially weaker party, and historically this has been the woman. It is not so much the cost of the proceedings that is daunting – but the aftermath. As the CII report shows, typically it’s women who absorb the risk: those in middle age can find themselves unemployable in an industry they may have thrived in before their marriage and/or having children.

“Once their children have grown up and any maintenance payments begin to dry up, they are often forced to rely on state provision. As Sian Fisher of the CII points out in the report, the historic support systems are receding: ‘We’re all expected to look after ourselves. On top of this, [women] may be caring for elderly parents and contending with their own mental or physical health issues.’ ”

But Reeves adds: “Divorce is a far less daunting prospect for women than non-marital separation: we still see women who have spent decades as a homemaker, raising children ... being forced to walk away at the end of their relationship with nothing. If she was married, the ‘homemaker’ has a right to share a partner’s pensions. However, this is a share of the pension assets at the time of the divorce.

“Following divorce, the financially stronger party – historically the man – can continue to earn at his full earning potential and top up his pension pot; meanwhile, the woman may have a reduced earning potential following years out of the employment market while she was building the home and bringing up children. And for women who are unmarried, there is no entitlement to a share in their former partner’s pension. Risk is inherent in relationships for women. While the gender pay gap between men and women in their 20s has closed, the gap opens and widens in later years – in quite a significant part because of women taking time out of employment to have families.”

A relationship, she went on, is the biggest financial risk women take. “Any woman embarking on a relationship should at least hear the facts and be aware of the risk she is adopting.”

Divorce is ever more costly: even basic court fees have doubled in the past few years and many women end up going into debt to cover costs, even if they do not use a lawyer. And legal aid reforms now rule out any state help.

Frances Hughes is a senior partner at London law firm Hughes Fowler Carruthers. In her long career in family law, she said, things have never looked so bad for women. “In terms of getting real access to justice, we must be back to the way things were before the second world war. The legal aid reforms have had a terrible effect on the courts, as has the reorganisation within the courts themselves.

“A lot of matters involving children are now heard by lay magistrates. There aren’t enough judges and the legal aid reforms have meant the courts are just jammed with the massive rise in litigants in person, which make for very laborious, gruelling and exhausting cases for all concerned. Women are the losers in all of this. Even in mediation, women tend to do badly.”

Nigel Shepherd, chair of mediation organisation Resolution, which works to help people find a constructive way through separation, avoiding hostile court cases where possible, agreed. “There’s this perception that men feel they get taken to the cleaners. Like any generic perception, it’s trite. Women do do worse out of divorce, but I don’t think it’s the particular failing of the system that penalises women; it’s more that the ability to recover financially after divorce reflects the wider inequality in society.

“A couple who have been married 30 years and divorce in their mid-50s, may split everything equally, but there is still a built-in inequality in the ability to rebuild from that point. We are seeing cases where the man is the lower earner but that’s not the normal way round; men are more likely to be the earners and divorce is not designed to be equal for ever. You go into it unequal and end up unequal.”

Dalia Ben-Galim, director at single parents’ charity Gingerbread, pointed to the impact of motherhood and the gender pay gap, as well as a “labour market that doesn’t work for people who want to work part time”. But she said taboos around divorce and separation were still intact. “One in four families in Britain is a single-parent family, and yet we still have our politicians holding up marriage, through policies like the married tax allowance, as this ideal. People feel they are failures if their relationship has failed. The reality is that people’s status changes throughout their adult lives for a whole range of reasons, not all of them within their control. Our lives aren’t static; they’re linear and dynamic. People need financial advice and emotional support: they need to know they and their kids will be OK, that they won’t be shamed and pushed into poverty.”

For Emma Cooper, having three children of primary school age means getting a job is an issue: “I gave up my job to follow my husband round the world with his career, and now I can’t get back into work.

“The biggest problem with divorce is that most people don’t agree, and that’s why they’re getting divorced. If I had any advice for women now thinking of getting married I’d say never, never, never give up your financial independence. No matter how difficult it may seem, keep one toe in the water: it may make the difference between sinking and swimming.”