So what is the right way to combat this if you’re a woman? Mostly by not sweating it. You can’t control what a man does; you can only control your actions and reactions to him. Better yet, try approaching each new guy with the blind confidence that he’s going to adore you. After all, men love confidence. Alternately, the more you worry about how often he’s logging on, who else he’s dating and why he hasn’t taken his profile down after two emails with you, the more likely you are to come across as needy.
Frankly, I think this is way too much analysis for a pretty simple situation. When a guy is crazy about a woman, he does whatever is in his power to make her his girlfriend as soon as he's sure. If he fails to do that, she’s just ignoring the writing on the wall.
It all comes down to behavior: act confident, stable and engaging, and you're sure to have better luck with online dating.