I have a theory about Jacob's behavior in Eclipse... why he acts like a jerk sometimes... like "sam's" Jacob
Jacob is using a mask in Eclipse. This mask covers the real Jacob... it makes him cynical and a jerk...Jacob is trying to protect himself from Bella.
I know that right now it sounds kinda stupid... and i'll try to explain better
Jacob is trying to protect himself from rejection (if you read ch.9 and 10, BD you'd know what i mean). He knows that Bella will reject him if he says anything and he know he wouldn't stand it, the pain will be too much for him to bare.As you know, he is trying to delud himself that Bella wants him too (like he says in Bella's graduation party, Eclipse, Ch. 17)So everytime he thinks he is going to show his true feeling, to "confess" to Bella (like when he says he is in love with her and she is kinda mean to him. Eclipse, Ch. 14 & 15), he stops himself. He don't want to get hurt...So he becomes the jerk that you all know in Eclipse.
Also, Edward is more mature (he is 109) and Jacob is fighting for her...the way his 16 years allow him...he just wants to make his point clear and snap Bella out of her obsession for Edward for a while just enough for her to realize that she loves him too...and she can stay with him and be happy and alive and have babies and stay with her family and enjoy a delicious barbecue ...You need to fight for who you love ..and if you see the whole picture..he is fighting for Bella's love with another man, but at the same time, he is fighting to keep his loved one alive...
I have a few exampls:
""What's the matter with you, Bella?" The joking bravado vanished from his face, reaviling my Jacob underneath, like pulling a mask away" (Eclipse. Ch, 21, Pg. 425)
"...You're my best friend. At least used to be, and still sometimes are.... when you let your gourd down" (Eclipse, Ch. 21, Pg. 426)
"He smiled the old smile I loved. "I'm always that.", He promised. "Evenwhen I don't..... behave as I should, Underneath, I'm always in here." (Eclipse, Ch. 21, Pg. 426)
I know it's all from the same chapter and the same pages but these are the best examples because he let his "gourd" down....And it keeps proving it self in BD... because he is not the same there...
This is what Stephenie says about the subject in her website:
"Jacob doesn't have a tragic flaw. He has one goal and one hope. His goal is to save Bella's life. His hope is that he'll win her heart in the process. He fails at both. But that doesn't mean he regrets trying. If he could do it over again, he'd do the same thing. Jacob couldn't live with himself if he didn't give saving Bella his best effort—he knows it's going to hurt when he loses, but he knows it would hurt worse if he didn't try. Does he do everything right? Heck, no! But he's sixteen and he's making it up as he goes along. Those who are upset by some of his tactics should consider his youth and the fact that he is, after all, right. Bella is in love with him. (In the end, it's truly healthier for her to be aware of this as she goes forward with unalterable decisions.)"
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