By Elise Nersesian

It happened slowly, over time. Relationships became less defined, and now it's often hard to know if you're actually in one. "Even if a guy acts like a boyfriend, he may not be committed," says Dr Scott Haltzman, author of The Secrets of Happily Married Women. "Online dating gives you so many choices that some guys prefer to keep their options open.

That's where Facebook comes in—not only does it connect men with new potential mates, it also keeps them in touch with old flames. "Our studies show that 80 per cent of people keep in contact with their exes through social-networking sites," says Dr Amy Muise, candidate in the department of applied social psychology at the University of Guelph in Canada "With all these reminders of the past, it can become harder for men to live in the present and make their relationships official."

The provider complex

But perhaps the biggest factor that's keeping men perpetually single is the economy. Significantly more men than women have lost their jobs in recent years. Understandably, guys feel overwhelming pressure to focus solely on their careers. "Many men have decided they simply can't afford to have a girlfriend right now," says Dr Bethany Marshallauthor of Deal Breakers. "They don't have the money to buy expensive dinners or fancy gifts." Nor do they feel they have the time or energy necessary for making a relationship work.

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As a result, many couples (and we're using that term loosely) fall into a gray area that sort of resembles a relationship but lacks the exclusivity and respect that a real romance requires. And this state of being may suit men better than women. "It's important to women to know where they stand," Marshall says. "They are relational by nature and need to know their role with a man in order to feel comfortable."

How to make him your boyfriend

According to research, women have a greater chance of landing a boyfriend when they don't have sex on the first date. "Even if he's trying to angle his way upstairs, men actually enjoy waiting," advises Haltzman. Log three or four dates before sleeping with him. If that's too retro for you, at least limit the number of nights you hang out. "Don't skip yoga or happy hour just because he wants to see you," says Marshall. "Not always being available keeps the mystery alive."

Also, when he asks what you want to do on a date, throw out something low-key, like dinner at a bar or a bike ride. That will take the pressure off him financially, and you'll appear fun and unpretentious—qualities all men admire.

Done all that and he's still not committing? It's time to articulate your desires. "Guys may hate 'the talk,' but it's fair for you to express that you would like to be exclusive," Haltzman says. Try saying something like, "I'm having fun with you and I don't really want to see other people anymore. Do you?" If he says he can't commit, break it off. Sometimes, realising you're slipping away is what gives him the kick in the butt to hold on.