What I have been fighting are the following assertions.
A) that what happened at the wedding was entirely Jacob's fault
B) that Jacob came to the wedding with the intent of continuing to fight for Bella
C) that Jacob didn't put out a concerted effort to make it a special evening for Bella
D) that Jacob simply flew off the handle with no lead up
E) that what happened at the wedding makes Jacob a bad friend
F) that Jacob didn't think he could handle it and didn't care if he caused a scene or got angry
G) this is the big one. That what happened at the wedding should be considered an example of who Jacob truly is, at heart. I have seen a lot of the people who argue this say that ONLY the argument should be considered. But, if you add in the rest of the conversation, you see someone trying very, very, very hard, but you also see someone who is inexperienced in handling these situations, someone who's incredibly stressed out, and someone who acts overemotionally to some very disturbing news.
You also see Bella have a little temper tantrum of her own before his, but of course no one mentions that.
HOFJ, believe it or not, I agree with almost every single word in this. Very well said!
The way I see it, Jacob came to the wedding to be Bella's friend. To an extent he had accepted that Bella would marry Edward. Or..What I will call it, he believed he had accepted it and could handle it. He still loved her, and I still think a small part of him was hoping that she would be his one day. But he did not come to the wedding with that in mind at all I think. He stayed away for such a long time. Why would he come back to cause trouble? If he believed he was still not able to handle seeing Bella with Edward, he would not have come back. The last thing in the world he wanted was to put Bella in any kind of danger. Jacob was just like Edward in that way.
It was the information he got a the wedding that made it all wrong for him. The thought of her having a normal honeymoon with her vampire husband, was too much to handle. Now as I've said before: safety first, but I also think that it triggered an amount of jealousy on his part. Not that he came to the wedding with the intention to fight for her, but at the wedding he realized that he was loosing Bella one way or another. What happened was wrong and dangerous. And it should not have happened. He should not have shaken Bella or whatever he did, or threaten Edward. That's really undebateable. But I agree with, hofj. This does not make Jacob ultimately a bad friend. He was young, in love and scared for her life and bit jealous/angry. He had been a good friend to Bella for a long time. What he did at the wedding was a huge mistake. But the way I see it, he didn't mean for it to happen. This does not make his behavior in any way right, but still I want to give Jacob the benefit of the doubt and say that he never intended to cause any harm at the wedding. Now this goes on to prove that Jacob wasn't in control of his emotions the way he should have been. But he didn't know that at the time, I think. Like hofj said, he was trying so hard to be a good friend. He tried to put a smile on her face when she looked like she was about to cry. He asked her if she was happy, and said that was the main thing. For a long time he put his own feelings aside.