This was written in about half an hour, and only read through once for errors. Tell me if there are any, and I'll fix them. Not the best I could've written, but it's something. I cut it because I thought it might get a little long on friends pages.
When you're not particularly interested in a character, or when you aren't obsessed to the point where you think about the characters you don't even like, you tend not to pay attention to them. Or, like some people, never bother to look beyond what you see on the television screen, and just take things for the way they appear.
For this reason, many people seem to think that Tara is shy and weak. Obviously, I think differently.
It's true, Tara was very shy. At first. But it's clear that once she gets to know people, she's no longer nervous around them. She can talk without stuttering, and doesn't keep her feelings and thoughts to herself. After season five's episode "Family" Tara was finally fully comfortable around all the Scoobies, and not just around Willow. We also learned from this episode that Tara didn't have many friends before she came to college and met Willow. Although it's sad, it's also fairly typical. Not many bothered to look past her initial shyness, and once she was older, didn't want to look past her homosexuality. I think her tendency to be nervous around people she doesn't know came from one thing: Her family.
Almost everything I'm pointing out here can really be taken from same episode mentioned earlier, "Family." Her family, although they were moderately friendly to her in public, was not very accepting of her in private. Once they are alone in her dorm, Tara's father reprimands her for continuing to use magic, and lets the audience know that she wasn't open about it at home. Her cousin, Beth, also catches her alone on campus, and lets us know that it's not just the magic they look down on her for, it's her sexuality. Although they obviously don't like magic, they seem to use it as an excuse to further look down on her, when in reality what they really have a big problem with is the fact that she's gay. If she had been straight, I don't think they would be quite as against the fact that she continued to use magic.
Then there's the fact that they had her believing that she was part demon, which seemed to serve two purposes. One was to try and discourage her from using magic. The second was to keep her living at home, so she could do housework and other "women's jobs." They claimed they could control the demon inside of her, which they tell her that her mother had as well. And she believes this, because they've been telling it to her all her life. Initially it was probably just to keep her from getting into magic. Which happened anyway. But then, her mother got sick, and eventually died. No more woman of the house to clean up after the men and to make them meals. So they wanted Tara to stay, yet they wanted her to leave at the same time. So they let her go to college, because they thought that she'd lose interest in magic if she went. Also, I suspect they wanted her to be able to get a good-paying job so she'd make lots of money that her father could take away from her.
The only person who seems to have been nice to her is her mother, and possibly her grandmother if she ever knew the woman. They're the only people she ever mentions before her father, brother, and cousin come. Her mother was into magic, and likely didn't hate her for the fact that she was gay. Seeing how the men in their family were, she was probably relieved that Tara could possibly try to get away from all that once she was older, and find a woman who cared about her. Which, of course, did happen. Yay for Tara.
So, my main point here (yes, I have one) is that Tara isn't just the shy girl people perceive her to be. She was shy at first, but who wouldn't have some trust issues after growing up in her household? After meeting Willow and then the Scoobies, she seems to shake off her shyness, and becomes more open to other people. Also, Tara is in no way weak. Just look at what she went through for eighteen years of her life. Her father then brother weren't very nice to her, her mother died, and she was stuck always doing the "woman" work around the house because her family was stuck in the 1800s. Then, when Willow started using magic against her, she left her. A weak person would have stayed, but Tara left. She knew what she had to do for the sake of herself and the people around her, and was strong enough to be able to do it.
Tara is a strong character. So people need to not write her as always weak and afraid. That's the way her father wanted her to be, and she left all that when she came to Sunnydale.