I believe Jodi's downfall was due to the choice she made to use her beauty to manipulate men as a life strategy instead of understanding that "a man is not a retirement plan." Her goal of attaching herself to a prosperous man and making herself indispensible to him sexually failed because eventually, even shallow men are smothered by her possessiveness and repelled by her cold, calculated mirroring of their interests.
Remember when she was still in high school, she marches up to a strange man at a carnival and then chases him using warnings of a religious Armageddon as the reason for repeatedly calling him. Jodi used religion as part of the chum she threw in the water to make herself look "deep" or "spiritual", i.e., desirable as a wife.
When these men didn't think marrying a *advertiser censored* queen was a good idea, she became furious and felt used, felt like a prostitute. Those who have tried this strategy and even some who become prostitutes can be shown that their emptiness can be filled by developing their own interests and skills and a life that reflects their own core beliefs.
The sociopath has no such core and is just a manipulative actress. Jodi could have become a wedding planner, but it's a lot of work and you have to have a schedule, make appointments and keep them. That's a high-paying job, but she really wanted to be a trophy wife and felt entitled to the man of her choice because of her beauty and pseudo personality. So she pretended to be a photographer. There is no evidence that she sold even one photo, let alone supported herself this way.
I think she was actually turning tricks to support herself.
Jodi hung on to MM until he found someone else, hung on to DB until she found someone equally rich/attractive who might marry her. You notice she was perfectly willing to leave DB AND A CHILD that she had lived with as a stepmother for some four years-- no bond. SHe was climbing a ladder and he did not want to marry her, even if she was a three-hole wonder.
When Travis put her in a rented room and booted her out of his glamorous lifestyle, of course she could not stand the humiliation of being his castoff. Seeing him with his new love, probably a Mormon virgin. She had offered him her kinky, well-used lady bits and he passed. Also, remember that his rejection meant she might not be so "eligible" in Mormon circles or at Prepaid Legal. And they were the only circles she had in Arizona-- even her roommate had rejected her because of her promiscuity and violent behavior. She knew everyone in the ward knew it was her. He was going to get off scott free and everyone thought she was a *****.
I think she was steaming over this and when she went down from the Executive Director's Big Ring dinner back to her grandmother's spare room and life as a waitress, she was incensed. She would not be powerless, she would show Travis how powerful she was. She would get her revenge by ruining his oh-so-perfect life as a hypocrite.
IMO she tried to blackmail him and when that failed, she felt she had to kill him to keep him from telling people what she had done with the sex photos (which I believe were staged by her). She would be excommunicated from the Mormon church, banned from Prepaid Legal and life at Grandma's would be it.
What is amazing to me is that sociopaths think they are so much smarter than everyone else. They actually believe that people cannot see what they are doing. "Duping delight" is absolutely right. It is a form of entertainment for the sociopath with great satisfaction afterward, like you or I would enjoy a terrific meal and a fine glass of wine.
WHen you have one in your family, it is terrifying to see it up close. My heart breaks for Travis' family. I know what it's like to live with a scar like that. I lost a son the same age as Travis and I think of him every day even though it was almost twenty years ago.