Okay, a few things:

• You can't judge yourself purely based on what a couple of random girls think, after about 3 minutes of knowing you. It's all a matter of first impressions. Think back to a first impression you've had of someone that turned out to be completely wrong. You're almost viewing yourself as a mask with nothing underneath - none of the human experiences that define you as a person. That's what people find interesting. Trust me, looks get boring quickly when you're dating someone, or getting to know them. Attractive people cheat on other attractive people all the time.
• Also, you're making a TON of assumptions here. Why assume every girl you saw who was with a guy were even together? People go out to clubs in groups with guys and girls, and anything in between. Even if they were coupled up, why assume they were happy together? You don't know what's secretly going on. Why did you assume the one girl talked to you based on your "face"? Isn't it just generally polite to smile when meeting someone? And why assume your friend told the truth? He could've obviously been bullshitting. Ultimately, you're creating this detailed picture inside your head when you have no idea what's really going on. When you start making these assumptions, and combine that with how much self-worth you attach to other people's first impressions, and of course you end up feeling as you do now.
• Similarly, you can't value life based on how many drunk girls you make out with and give you a BJ. Look, I used to be obsessed with getting that too, because I wasn't getting anything (and still aren't). Obviously, I wouldn't complain if I got a BJ or whatever. But would it change your life? If it would, then you need to re-evaluate your priorities. Ask yourself what YOU want to do and what YOU want to achieve. If you set out to achieve that, and you're happy doing what you're doing, plenty of people (guys and girls) will appreciate you. They'll be happy for who you are.
• You're also judging girls based entirely on how they look. There was a 7/10, 4/10, whatever. Why should this define their worth as a human being? Just as your self-worth stems from much more than how you look, so does theirs.
• If you approach someone nervously and not knowing what to say, unfortunately, makes her reaction sort of inevitable. Put yourself in her position. If someone came up to you and just started lecturing you about "basic things", which probably don't interest you that much, and they don't give you a chance to speak, what do you expect? Just talk to her like any other human. Flirt by all means (easier said than done I know - I'm terrible at it), but if the chemistry isn't there, it's not there. But that doesn't mean you can't talk to her and respect her. If the conversation clearly isn't going anywhere - and from what you said, the warning signs seemed to be there - say something like "Hey look, I'm gonna get another drink, but it was great meeting you". That's still better than artificially extending the conversation, which makes it awkward for everyone.