Everyone is how they are in the series. Jacob is a wolf, and is part of the same pack. The Cullens are vampires, and Bella is a human. Their characteristics are all the same, and the Cullens & wolves still hate each other.
BPOV:
"C'mon Bells!" Jake yelled as he grabbed my hand and pulled me into the blue-green waves of the ocean at First Beach.
I shrieked. The water was absolutely freezing! But that didn't matter. I was with the boy I loved: Jacob Black, and therefore I was happy. I had been dating him for over a year, and it was three years ago that I chose him over Edward Cullen. Edward & I were very serious, and if he wasn't a vampire, I think I would still be with him. He constantly would remind me how dangerous he was, and how I shouldn't be with him. I didn't believe him until the one day he lost control. I remembered it clearly . . .
Edward and I were in the woods behind his house. His usually amber eyes were onyx, and he had bruises under his eyes. It surprised me that he hadn't hunted, and that he was so thirsty, but I knew I had nothing to worry about; Edward would never hurt me. I stretched up on my toes to kiss his flawless lips, but he grabbed my face in his hands and stopped me. He sniffed my hair, my throat, and my wrists. I always knew how my blood "sang" for him, but I figured he was just being affectionate.
Suddenly. I felt a piercing pain stab through my wrist, and I screamed a blood-curling scream. My eyes were beginning to close, but before they did, I saw Edward, eyes glowing red from my blood, biting into my right wrist. Carlisle Cullen, Edward's father who had supreme self-control, was suddenly at my side, along with Emmett and Alice (Edward's adopted siblings). Emmett and Alice held Edward back as Carlisle bent over to suck the venom from my wrist. It felt as though a fire was burning my body, and I couldn't put it out. As much as I screamed and thrashed for it to be put out, it just got worse. Just as I thought I was beginning to slip away, I began to feel more and more energy coming through me. The fire was beginning to fade, and eventually, it stopped all together.
When I was completely conscious, I realized what had happened, and I knew the decision I had to make. I was beyond upset; I was truly in love with Edward, and it killed me to let him go. But I knew that if I didn't, not only would I be killed, but the Cullens would be forced to leave, and I didn't want to cause Edward any pain at all.
I wrote a note to him, and gave it to Alice to give to him. When I got home, Charlie, my father, told me that my best friend (at the time), Jacob Black, had called and wanted me to hang out. I called him back, and I headed down to La Push. As soon as I got there, I ran into Jacob's arms and cried. I explained everything, and he was furious. Not only did his tribe hate the Cullens, but he was upset at what Edward had done.
For the next few weeks, I spent every day with Jacob, and he was always there for me. We both soon realized that we were becoming more than friends, and neither of us did anything to stop it.
Finally, he kissed me, and I realized that I was in love with him, just like I had been with Edward. His kiss was so much different; his warm lips moved with mine perfectly, and he didn't have to restrict himself the way Edward did. It was nice.
The Cullens moved away (I don't know where), and that brings me to the present. It hurt just to think about that day when I left Edward, because deep down, I still loved him.
Suddenly, I felt burning-hot arms wrap around me, and I snapped out of my little daydream. Geez, how long had I been zoned out?! I looked up, and Jacob's russet-skinned face was barely two inches from mine. His dark eyes looked deeply into mine, and I instantly melted. He kissed me passionately, and I forgot about Edward for the moment.
"Bella, is this water too cold for you? We could get out if you want . . . "
"No, you can keep me warm," I said, with a smug smile on my face.
Jake grinned the grin that I loved, and kept his arms around me.
"So what were you thinking about? I swear, your mind must have been on Mars or something . . . " he said.
"Oh, um . . . it's nothing. Trust me," I lied.
Unfortunately, you didn't have to be a genius to know when I was lying.
"Oh come on Bells! You can tell me anything, remember? I remember when you told me about how you had a little crush on Barney when you were three years old . . . "
I had to laugh. "Jake! Shh! Fine. I'll tell you! I was just thinking back to my last day with Edward, that's all . . . "
His smile faded, and he growled at the mention of Edward's name.
"But don't worry! It's all right, you know I only love you," I amended.
"I know, and you know I love you too. I just hate what that stupid leech did to you," replied Jacob, grimly.
"Yeah, but it brought us together. I guess the phrase 'when one door closes, another opens' is true after all."
He agreed and we stayed in each others' arms for a while.
We finally got out, and with a final kiss, I went home.