Well she did become a leech
But for what price?
Losing your own family you've known since you were little, your mortality as well with it?!
From the beginning she met this guy who was "perfect" in her eyes (*snorts*) and believes that's all she needs to live for. Very clingy and she never cared for anything else. At least Jacob proved it wrong and she actually grew a heart to actually consider the possibilities of being with others. (She wasn't experienced in the love department and though Edward could all of that of her heart. It's called reality).
What about her father and her own best friend, her mother? What about her human friends? (Sure they leave to pursue other things, but it's not like Bella can visit them or anything)
And she led Jacob on and even Edward. Her lack of differentiating of what is wrong and what is right is horrible.
She lost much respect for having to be like that. But it's love what can she do about it? All I know is, she hurt Jacob badly by the end. (Before the part in Breaking Dawn when she gives birth to Nessie) He really didn't deserve it and even Edward himself had to grow a gut and stand up for himself. Heh. At least he was able to imprint.
Sure deciding on your own best friend (and lately figured out that you were in love with him as well) or the love of your life from day one....the way I said it right now makes it simple to answer but her situation was complex. I'll give her that, that it probably wasn't easy. But she didn't have to be a ***** through the process of it all. (Particularly to Jacob, and well it was like she used both of them)