Internet dating is hugely popular, with millions of us meeting new people and finding romance online – so why is it still viewed with suspicion?

Seven million – more than the population of Scotland. In 2009 there were 12 million first dates arranged online. Research by the Oxford Internet Institute suggests that 20 per cent of all married couples under the age of 25 now meet via the internet.

With numbers like these, you might believe that internet dating is now a social norm, as acceptable as booking a holiday online or bidding for something on eBay. But is that really the case?

Megan is 36. She began internet dating three years ago, and did so for 12 months. She signed up to a website, wrote her profile – explaining who she is and what she was looking for – then waited for a response. And she got one. Over the year she went on about 20 dates ("not that prolific") and, while she didn't meet a partner, she did make friends with a couple of men who she still sees.

But Megan, like everyone else who was eager to talk about their experiences, didn't want her real name to be used. She's not ashamed (why should she be?) but she'd rather people didn't know and that tells us that internet dating, something which millions of us do, is still viewed with some suspicion.

This ambivalence is one of the reasons that filmmaker Sue Bourne's documentary, Wink, Meet, Delete: An Internet Guide to Dating, is so fascinating. At turns funny, sad and beguilingly peculiar, what Bourne's film shows is the range of people who are looking for love online. Lots are having a great time, some not so much. Some have found internet dating liberating, others bruising. Whatever the impact, with thousands signing up to sites every day, there are questions to be asked about why people date online, and how it affects who they are offline.

"I liked online dating because you can make a list of demands – things that you want – but you can word it in a friendly way," says Megan. "I didn't want anybody who had kids or any kind of religious affiliation. I wanted someone who ideally had a dog." Megan only had two negative experiences "and they weren't creepy", one was just a bad date and the other was a guy who wanted to see her again even though she didn't want to see him. On the positive side, she found the experience to be a real boost to her self-esteem.

"It made me really confident to snag someone," she says. "Prior to that I didn't feel like a catch, but when people were responding to my profile, I did. In the pub I feel like the last person anyone would be interested in, I feel like I can't live up to what they expect. (Online dating] made me much flirtier in real life in a good way, in an honest way."

A survey conducted by MIT and Boston University found that 20 per cent of online daters admitted to deception, but when asked what percentage of others they believed to be lying, the estimate jumped to 90 per cent.

"I think it's really bad news to lie about anything," says Megan. "What kind of starting point is that?"

That said, from what Bourne found, using the most flattering photograph or adding a couple of inches to your height, is commonplace online. What's less explored is the emotional impact that internet dating can

have.

Bourne has made her name creating acclaimed films such as My Street, in which she got to know her London neighbours, and the tremendously moving Mum & Me about her relationship with her mother, Ethel, who has Alzheimer's disease.

Her interest in online dating came out of a chance meeting. She sat

next to a young woman at a film festival who happened to be on a dating site. Looking for a topic for a documentary, Bourne asked to meet her for a coffee to talk about it.

"She was so eloquent," she says, sitting in the production suite in Glasgow where her film was edited. "I came away from that almost in tears. She told me that she'd met a guy and they had corresponded. So much time and energy and hope is invested in this person that you haven't met that when you do meet it is hugely emotionally charged. You think this might be the one. When they met he was what she hoped for and it was all going really well and then at one point she saw a flicker on his face and she knew she'd lost him. She'd said or done something, although she didn't know what, and she was devastated. She didn't hear from him again.

"These are people at their most vulnerable who are putting themselves out there to be rejected. What is that doing to us?"

Bourne and her team made contact with 11,000 people. They then whittled it down to 300, then the final 12 who are featured in the film.

Bourne's skill is to put people at their ease to allow them to be completely open.

"I'd never seen a film that told me how you actually did internet dating," she says. "I didn't know about winking and I didn't know about how addictive it can be."

Finding the right people was hard, it took "months" and at times it was, she says, a nightmare, but she knew it had to be right.

"It's fundamental to what life is about – it's about relationships, love, loneliness. It's about how we live now and how it's affecting us. I didn't want to do anything salacious what I wanted to get at was how it changed people, how it affected them."

Bourne's film includes Gary, the estate agent in his late forties hoping to meet someone with kids so that, along with his children, they can become one big happy family.

Helena, in her early twenties, is trying to get over being dumped by a boyfriend who was internet dating behind her back, while Anne, in her fifties, is a widow looking to find romantic love, "someone who I can cherish and who will cherish me". After splitting from her second husband and being single for two years, Alison, 47, decided that internet dating might just be the way to meet someone.

"I had done the usual, friends taking me out to bars and meeting guys," she says, "but honestly, most of them were married or attached but pretending not to be. I just thought there must be a better way, but I have three sons so I didn't get out that much. So I thought I'd have a look at internet dating."

Alison, like Megan, found the experience both exciting and a boost for her confidence.

"You tend to talk to people that normally you wouldn't have the courage to talk to. If you saw them across a bar you might think that he or she was out of your league but online it's different. You think, well, they can't really see me and the photograph that you use is always the best one you've ever had taken. As is theirs. You feel more confident because you're anonymous and safe."

On her eighth date, Alison met Callum, 44. They had been corresponding by e-mail for a few months, a part of the process that they both enjoyed, but Alison was seeing someone, which she told Callum and, given that their profiles didn't quite match up – Callum didn't have any children and didn't want any, Alison had three – they just stuck with e-mail. Then, when Alison's relationship ended, they decided it was time to meet.

Alison was prepared to be disappointed as she had been before.

"I thought it was just going to be another case of nice pictures, so I deliberately dressed down in old combats and this horrible top," she says. "But that time I wasn't disappointed at all."

Alison and Callum have been together for more than two years. "He still says he's glad that I made such an effort for him on that first date," she laughs. "And we still laugh about the fact that we're totally incompatible after two years and three months."

For two other couples in Bourne's film, internet dating was also a total success. They found each other within a matter of months, without enduring too many bad dates, reading too many profiles that turned out not to be quite the truth, or perhaps worst of all, having people just "go silent" on them. It's not that way for everyone.

The positive aspect of being able to say exactly what it is that you want has a flip side – people also say what they don't want. Both Megan and Alison say that at times it was hard. What's more, the sheer volume of people looking to connect online can mean it's difficult to settle with one person, and tempting to become a serial dater.

According to a study by Stanford University, "in the next several years the internet could eclipse friends as the most influential way Americans meet their romantic partners". It seems reasonable to assume that the same could well happen here. It's why Bourne's film is both fascinating and necessary. But while you watch, it's worth remembering the success stories.

"I look at my past relationships and with the best will in the world, the old clich of meeting someone and falling into bed and then making a go of it is completely the wrong way for me," says Alison. "It's because Callum and I started talking to each other in the way that we did, by e-mail, that we knew an awful lot about each other's likes and dislikes, and it feels like we've got a really solid foundation to go forward from.

"Maybe people feel it's not romantic, that it's calculated, but it's really not because you get the background and then the romance can happen if the chemistry is there. I'd encourage anyone to do it. I think it's a great way to meet people."

• Wink, Meet, Delete: An Internet Guide to Dating will be on BBC2 Scotland tomorrow at 9pm