Re: Online dating girls who are online dating lots of guys?
You're becoming outcome dependent, which means that you're already clingy. Also, if she's taking a long time to respond, she has tons of guys constantly emailing her, and she spontaneously shows up at your place when you think she's going to flake, then that's an obvious sign that you're not the only guy she's sleeping around with.
Now, how to you make it so that she is only focused on you?
That's tough. I'd say the best way is to invite her on a date where sex is involved in now way, shape, or form, and really put out. Impress her, make her laugh, and BE SOBER. She has only seen intoxicated you, so show her how great sober you can be. If the date goes well, it might put you a step above the other guys she's talking to.
"There is no better than adversity. Every defeat, every heartbreak, every loss, contains its own seed, its own lesson on how to improve your performance the next time." - Malcolm X