The movie begins with a court scene, the judge admonishing Melinda for her behavior and advising her to attend therapy to avoid harsher consequences such as jail time. She glares at the other side of the courtroom and has to be nudged by her attorney to reply she understands. She attends a therapy session resentful at having to be there and begins telling her story of betrayal to the court appointed counselor. She begins by describing how she met Robert as they crashed into each other on campus. Their schoolwork gets exchanged accidentally and Robert locates her dorm room to return her papers to her and reclaim his own. There is an instant attraction and he offers to help her with her paper as he's already taken the class. And they begin working together and seeing each other. Melinda fails the assignment and as she's telling Robert about the sacrifice her mother is making to send her to school she sees her two sisters walk up. They give her the news that her mother has passed away.
Robert comes to the house after the funeral services and her sisters give him the interrogation introducing him to Melinda's ex-boyfriend from high school. Robert leaves to return home appearing to feel out of place but Melinda runs after him and offers to drive him home. She takes him to an old RV he says he lives in that is housed in the driveway of his aunt. They talk and eventually walk into the bedroom where she advises us she loses her virginity. They are a couple now and Melinda has been left her mother's house and $350,000 in insurance that her sisters advise her not to tell Robert about but by then she has.
On one of their dates he tells her that he plans to sell a battery he's invented that will be revolutionary. But he's concerned when the company he has been trying to sell it to contacts him he will have no way of making it to their office as he has no transportation. Melinda believes it's her responsibility to purchase him a car to ensure whenever that call comes he will be able to get there. But she notices almost immediately that the frequency of his calls become less and less. And she begins to suspect he may be cheating on her. She drives over to his RV and sees a hand pressed against the window and hears the sounds of love making. Quite naturally she turns her jeep around and rams it several times into the side of the RV until it falls on its side. Robert escapes through the bedroom window and pulls a young girl out we later learn is Diana. Melinda throws a brick through the window of the car she purchased and passed out. She explains that when she was driving the jeep into the RV she also hit her abdomen on the steering wheel causing internal injuries, internal bleeding and forces her ro have a hysterectomy.
Robert attempts to see her in the hospital but her watchdog sisters tell him to leave as they blame him for what happened to their baby sister. Her friend Sara promises to let him know how she is.
When Melinda comes home from the hospital to convalesce Robert calls out to her from outside and her sisters are livid. She begs them to let her see him so she can find out why he did this to her. He comes in and apologizes telling her that the girl met nothing to him and he has no idea why he did that but he would never do it again. Melinda forgives him and they start back to seeing each other. On another date Robert lets her know he will not have the money to complete his last two semesters and she opens her checkbook up at the bursar's office to pay his tuition. They get married and her money from her mother dwindles down to nothing. Robert has a felony from when he was a teenager and has difficulty finding work with a record. Everything they have goes into his battery invention and Melinda works two jobs and mortgages the house to support him.
18 years later the house is about to be foreclosed and the company Robert has been sending videos and letters to every week all these years still hasn't responded to him. He finds out that Diana from college has become an admin to the President of the company and he seeks her guidance on what to do. Melinda's sisters come to the house to confront her about the foreclosure and her brother in laws offer Robert a job. They have a significant client that will pay for their delivery service in advance if they just comply with his delivery requirements. They explain that they will give the money to Robert and Melinda to keep the house in exchange for him working for them. Robert agrees but tells Melinda he's disappointed she didn't defend him to her family.
Robert is now a delivery driver for his brother in law's business and loading his truck for the day. Melinda's sister gets in the truck to check the odometer and finds a women's wallet. It belongs to Diana. The sisters rush to Melinda's office job she got from her friend Sara to tell her Robert is being unfaithful again. Robert receives a call from Diana that her boss wants to see him at 11:30 with the battery prototype and he ditches his delivery job to go home and get ready. Melinda has returned home to confront him for being unfaithful and won't believe anything he says. They begin to fight and her sisters arrive in time to pull her off of him. He leaves for his meeting and her sisters take her into the house.
Robert goes to the boardroom and is offered $700,000 for the battery and all the rights to the research. He is devastated. He believes his work is worth millions and wants to keep his licenses and copyright. He turns it down and goes home to tell Melinda what happened. She's in the living room smoking a cigarette surrounded by her sisters and brother in laws. She tells him it's over. And has all his possessions in a pile on the floor. He begs her to believe him that he hasn't been unfaithful and tells her about the offer. But she tells him to leave.
Melinda loses the house and has to move in with her sister. Robert moves into a shelter and lies about his felony to get a job as a dishwasher. Melinda begins dating her boyfriend from high school and on one of their dates sees Robert washing dishes in the kitchen. They go to the attorney's office to sign the papers, Robert again asks her not to do this but she refuses to speak to him. While at work one day Robert gets a call from Diana asking why she can't reach him. He tells her his phone was stolen and that he's living in a shelter. She tells him she's coming to get him. He begins staying with her and one day she comes home from work with paperwork and a check for $75 million dollars. The company met his demands and paid for his work.
Robert comes to Melinda's job with roses and apologizes for everything. Gives her a check for $10 million dollars and the keys and deed to her mom's house. He tells her he loves her. She returns home to her sister's house and they are all there with her high school boyfriend. She shows them the check and blames her sisters for causing her to lose everything. She insults everyone and goes to her bedroom. Robert is in his apartment overlooking the city in a tux and there's a knock at the door. Its Melinda. She thought that his visit met he was still in love with her and she tells him she still loves him and opens her coat to reveal lingerie. Diana enters the room and introduces herself as his fiance. Melinda leaves and begins stalking them online. She's now back in her mother's home with a mattress on the floor and a table with a laptop surrounded by empty liquor bottles. She takes Robert to court demanding more money and the judge tells her that Robert has been extremely generous and he throws out the case. She finds out where Diana's wedding dress is and goes to the shop pouring acid all over it.
We return to court where the first scene began and she learn that Diana and Robert are expecting a child. Melinda's sisters ask Robert and Diana over to warn them that Melinda is dangerous. She comes over while they are there and becomes irate that they have the two of them at their home. She drives away angrily. Back at home still stalking them online she sees they are getting married and have purchased a yacht.
Robert and Diana get married and sail away on their yacht. They have a full staff waiting on them and they are lying under the stars. Diana goes below deck to run a bath and Robert stays on deck to listen to Nina Simone and finish his champagne. Melinda walks out wearing Diana's wedding dress and wielding a gun. She orders the staff to jump into the water and for Robert to go with her to tell Diana its over. Melinda in her rage shoots him in the abdomen. Diana hears the shot and runs out to see Melinda with the gun. She runs away and Melinda runs after her demanding Diana give her the wedding ring. Melinda feeling that the apartment, yacht, ring and Robert all belong to her. Robert pushed her off the boat to save Diana and orders Diana to turn their yacht off and take the small boat to save the crew. Melinda returns soaking wet and grabs an ax. She follows a bleeding Robert to the front and steps into the chains of the anchor lifting the ax and bringing it down on Robert's leg. Just as she is about to do it again, Robert presses the anchor release and drops anchor pulling the chain Melinda stepped in causing it to pull her off the boat and into the water. She drowns. Diana and the crew return and begin to help Robert. And the movie fades to black.