To this, Sue King, national councillor for the lone parents' organisation Gingerbread, and herself a single mother, adds that a crucial stage is to take care over that vital first meeting. "Some children welcome the new partner; others feel threatened. Every child's an individual, and their response depends on their age and on why their parents' relationship broke down, but it's also influenced by how they are introduced. If you're in bed with a new girlfriend and your child suddenly walks in, it's going to cause a shock. You need to work out how to deal with your sex life in front of your children, and to reassure them and be honest with them. If they get to know someone first, they'll usually respond better than if they see mummy sleeping with Fred one week and George the next."
Her own experience suggests there is no guarantee that matters will proceed according to plan, even if the introductions are handled with impeccable decorum. "My daughter would have loved to have a stepdaddy, but there were some people she disliked on sight. She took an intense dislike to one of my oldest friends but loved his twin brother. These responses may seem arbitrary - some children just dislike men with beards, for example - but you need to take the child's view seriously."
For parents who have always been single, the arrival of a lover can present added difficulties because of the intensity of the relationship with their children. Annette, a young woman who lost contact with her father after he went to prison when she was one year old, remembers encouraging her mother to marry again because she dreamed of a bigger house. But when would-be candidates arrived, her response shifted to one of outright hostility, mitigated only by the treats they would offer.
"My brother and I did everything we could to chase these chaps off. I once vomited in one of their cars, and Paul tried to strangle one and poured boiling water on another. So Mum started getting babysitters and going out instead, until Paul tried to drown himself after saying he wanted to marry Mummy himself."
Even when the children welcome the new partner, there is frequently the additional obstacle of the "ex" - the child's other parent - especially for those recently divorced. Michele, a social worker well versed in the trauma of family breakdown, began dating James a year after his divorce, but insisted she would not stay the night until she had developed a solid relationship with his eight-year-old son. "The problem was with his mum - she used to phone James late at night or at the crack of dawn when we were in bed together, just to swear at him. She really picked her times and it drove me bananas."
Another barrier is the sense of hopelessness which envelopes many lone parents who become overwhelmed by their circumstances. Bernadette, the once-middle-class single mother of six-year-old Ben, lives in a poky council flat and blames her diminished sexual confidence on her bleak circumstances and sparse social network.
"Ben's dad pays maintenance which he doesn't declare because then I'd lose Income Support, but the catch is that if I get a new lover he'll stop paying. He sleeps over once a month, which is cool with Ben, but it's not enough for me. With other men, and there aren't many, it's just wham, bang and out of here before Ben wakes. Most of them are no good anyway - some are welfare cases themselves and they just like the look of my horrible flat and others are grossed out by nappies and stuff."
At first she had "romantic notions" about going it alone, but few of these were met. "I used to be a spunky girl with lots of admirers, but the whole business has made me quite depressed and I struggle to keep my tail up. I went for therapy and even got a free breast op as a result, to boost my confidence - which I would have thought was insane a few years ago."
Her neighbour, Gloria, rolls her eyeballs at Bernadette's defeatist approach. Once a week her cousin babysits overnight and she goes clubbing. "I get all tarted up and when one of the girls asks me where I'm going, I say: `To find you a new daddy, babe'. Jade takes it seriously but Stacey just laughs. She's seven, so she knows what's what." Gloria insists that, in reality, finding a "new daddy" is low on her list of priorities. "If it happens, it happens, but right now I think it would cause more problems than it would solve. I usually stay the night because I don't want baby's bottles and bed-wetting on my mind, but I'm always back the next morning and I'm usually in a much better mood because I need it. I'm a mum, not a nun"n