Character Dilemma

Ugh. Okay. I'm gonna rant and whine and complain and hope that a wiser, more experienced writer will have pity on me and decide to give me words of wisdom.
Here I go.
I have a character in my story. She is quiet, thoughtful and self-sacrificing. She hates sweets. She holds grudges. She puts many things before her own well-being, which can be a pretty bad thing. She is a good debater, but prefers to stay out of debates. I guess that kind of gives you a general idea on what kind of person this girl is.
The thing is that I feel like I'm missing something. I feel like she's boring. See, she's the protagonist in the story and everything is seen from her perspective, but nothing about her perspective is really engaging. She has a good sense of right and wrong, and is very down-to-earth. Yeah, she does have weaknesses and flaws, but they don't help in making her any more interesting. 
Normally, I create characters with crazy, strong personalities (like a fun-loving, eccentric adventure seeker or a reclusive, irritable grouch). I keep thinking that those are the interesting characters, that those are the characters that make a reader want to dive into a story. This is the first time I've created a character that is shy instead of boisterous, thoughtful and quiet instead of impulsive or eccentric.
The problem is that I don't know what I have to do to add color to her. Writing from her perspective is no fun- I really don't feel any strong connections to this character at all. Usually I try to add something in a character that relates to me- a habit, a fear, an experience- so I can connect to him/her. But none of that works. She's still boring. I've tried to give her stronger qualities, but I end up making a mess of her and ruining the entire characterization. Still boring in the end.
So how can I add zest to an otherwise timid, introverted character? How can I make her point of view interesting and intriguing? And most importantly, how can I turn her into a character that a reader could root for?