4. She Flirts with Other Guys In Front of You
4. 她在你面前和别的男生打情骂俏

Now this can mean one of two different things. The first possibility is that she's attempting to gain your attention by making you jealous. If this is the case, you're good to go, apart from the fact that you're dating a manipulative b*tch. If you're cool with that, then good for you. However, the sad alternative is that if she's not trying to make you jealous, then she is literally flirting with those guys with every intention of getting laid. And it's all happening right under your nose. Super.
这种情况只有两种可能性。洗具的结果是她想通过与别的男生调情来引起你的注意。杯具的结果是……你懂的！

5. She Signs Off Facebook Chat Moments After You Start Talking to Her
5. 你一上线她就隐身

Don't kid yourself man, at this point you know she's avoiding you. It doesn't matter what she says. If she logs off every time you attempt to talk to her, regardless of how long she's been online, then she's avoiding you like your parents avoided the sex talk back in the day. But on the bright side, at least she's being considerate in her attempts not to talk to you. I knew one gal that told me she had to go do some work, but couldn't even be bothered to log out. She even continued commenting on one of our mutual friend's threads, which I was also a part of. Needless to say, she and I aren't very close anymore.
世界上最可悲是事情是你对其隐身可见，而她在线对你隐身。

6. She Makes ZERO Effort to Look Good In Front of You
6. 她总是灰头土脸地出现在你面前

Despite what they might say, girls are vain. They want you to tell them how pretty they are. They might not "need" it, but they sure as hell want the praise. And when she stops desiring your approval and compliments, you're either married, or she's no longer interested (they're roughly the same thing; the only difference is that if you're breaking up at least you have the prospect of break-up sex - if you're married, you're just SOL).
女孩子总是虚荣的，如果她能够忍受自己在你面前素面朝天，那么估计她已经不在意你的赞美了。

7. Her Friends Have All Stopped Talking Her Up In Front of You
7. 她的朋友有意无意地向你透露她的毛病

This one is subtle, and not always noticeable, but if you pay enough attention and actually listen to her friends when they speak instead of blocking them out as white noise (novel concept, I know), you'll start to see that right around the same time she starts to drift away, her friends will stop making her look so awesome. Instead of saying how pretty she is and how funny her jokes are like they used to, they'll now proceed to start pointing out her flaws when she's not around (often at her request) to make her seem less attractive to you. It's their way of starting to let you down gently. And though it sucks, there are some friends of hers who will really go the extra mile and hook up with you so you forget about her, which opens up a whole other can of worms that I won't deal with. But it's a fun can of worms, indeed.
他们并非心存恶意，只是想让你慢慢放弃。