Why Can't I Make Friends?

Ever since I can remember, I had the most difficulty relating to others, specifically, forming and maintaining friendships.
So here I am, 18 years old, at a school with 2500 students, and I am, yet again, without friends.
But the thing is, I'm not shy. At all. I mean, no, I'm not obnoxious or loud. I don't tell people to their face that they're ugly or any of the sort.
I've joined clubs, in and outside school. I've talked to people in my classes. I smile (if the time calls for it) when I talk to people and I try to maintain a positive attitude. And still, no success. Everywhere I go, this happens. People just seem to avoid me. I brush my teeth twice a day, floss, shower daily, and generally maintain good hygiene by the way.
I have some theories, so maybe you could point out if one of them would turn YOU off, too:

1) I'm a verrry tall girl . At 18, I stand 5'10 and I'm bigboned (although I'm not medically overweight). I'm proud of being Dutch-American (although I speak English only) and know a lot of tall Dutch.

2) I am a MOOCH . I borrow money from people I hardley know (I usually forget to pay them back unless they ask me) and I'm always asking people to loan me pencils, pieces of paper, etc. I don't do this nearly as often as I did in the 9th grade, but it still haunts me to this day.

3) I wear a ridiculous poofy bun on the top of my head (lol) because my long, red hair is too curly and more importantly, the bun makes my forehead not look as low. You remember Mrs.Trenchbull from the movie Matilda? Yep.

4) I tend to wear the same two outfits (including shoes) every day . I wear the same color eyeshadow everyday, same earrings, necklace...they're not ugly or out of style, but I wear them EVERYDAY because I'm too lazy to go shopping..and I look fat in anything else.

5) As soon as I feel comfortable talking to somebody (like a group for a class project), I'll comment on every little thing. It's not that I ramble, but I just always make a random comment/complaint and I think people eventually get sick of it and go "yeah.......uh huh....yeah..."

6) My voice . It just doesn't sound like everyone else's. It sounds really slow and struggles to pronounce words right. I mean, it almost sounds like slurring. It just...doesn't flow like everybody else.

7) Delayed maturity . I think I'm sort of childish and out of the loop. I wouldn't watch ANYTHING but Nickelodeon and Disney Channel until I was 15. (Even then, if the shows weren't cartoons, I wouldn't watch it cause I'd think it was 'boring'). Now, I don't really watch cartoons. I watch normal stuff, like MTV, Friends, Judge Judy...

8.)I'm greedy and self-absorbed . When talking to people, I don't really ask about themselves. I usually just relate whatever they're saying to me. When I was younger, I used to be extraordinarily greedy. If there was a bowl of sample candies in the store, you could bet I'd scoop everything out (if it was free) and stash it in my pocket. And if a person on the bus dropped their groceries, I would never help them pick it up. I am a total bitch with poor etiquette. Now, I try to go out of my way a bit to help out other people now and then.

9) Earlier acts of stupidity . When I was 14, I'd do really stupid things. I'd maybe get TOO comfortable with people. I remember at a birthday party, this guy was being funny, nice, you know. I didn't have a crush on him or anything like that. Well, during Truth or Dare, I get too excited and hyper and dare him to lick the garage floor. I didn't even know this guy for more than 2 hours! Also, I called this girl up (I didn't know her at all) and just giggled and rambled about different types of beer...yes, I was drunk...and alone, how pathetic.. In German class, we were supposed to do some brief skit, so I'm doing it with this girl I don't even know, and thinking I'm funny, joke that she should work at McDonalds. I don't know WHAT possessed me to do that, I'm such an ass(hole), but I certainley didn't mean it. I tried to apologize to her, but she just looks at me like I'm weird. I totally don't blame her.

10) I'm a pest . When I get people's numbers for school projects, I don't use it JUST for the project. I'll call them if I'm sick and ask what the assignment was. I think I might be disturbing their privacy if I'm calling them 2 months after the project was over with..

11) LAST ONE! I laugh at myself ...lol.

Now, I've tried asking my family over and over if they can identify anything "off" about me, but they can't pinpoint anything. I strongly feel it's one of the above eleven. Pretend I was some random chick in your class. Which of these would piss you off or make you roll your eyes or say to yourself, "I'm not going NEAR that freak". Thank you sooo much for this.

One thing I can relate to...excessive commenting. I used to have trouble with friends back in high school. While people normally have 20 to 30 people they talk to/etc..i only had 3 or 4. What I learned over time, is that it's because of excessive commenting/complaining. You see something, and for whatever reason...you decide to make a comment on it. So people get really sick of that fast.

3 years out of high school, I'm a totally different person. I don't try to be different, I'm just changed. People say I'm 'sociable,' they're very comfortable talking to me about anything (including relationships), and they view me as a nice person who actually listens/cares.

But yeah. If you're Friendly so people are super comfortable talking to you, and you don't talk more than needed, you'll be good. Limiting talking will go a long way to help you. And keep up the hygiene part.