I don't think the jury needs to understand her motivation as well as we do. JM will remind them that the bottom line is she premeditated his slaughter, drove 1,000 miles to reach her victim, left to go adjust another man, lied lied lied lied lied, has shown no remorse whatsoever, and based on the what they've been hearing for months, blames the man she murdered for his own death.
And that's even before they think about her accusing Travis of pedophilia, sending that sickening letter to his family, irises to his grandmother, etc. etc.