Question: How on earth could it take as long five years for a possessive and controlling abuser like Mitch to first show his true nature? I get that with some abusers it can take a bit of time, but five years seems a bit of a stretch. Also, did Mitch really believe himself to be in love with Slim? It seemed to me that he was far more arrogant and greedy, rather than lusting.
Answer: In addition to the other answer here: Abusers often *do* believe that they love their victims. They have a distorted idea of how to behave and treat someone who they love. Mitch can certainly be arrogant and greedy, while also "loving" Slim in his own sick way. There are even non-abusive people who are arrogant and greedy, but love their partners and families.
Continuity mistake: When Slim and Mitch embrace after she finds out he is cheating, she is wearing a purple dress/robe, but for some weird reason after the fade out, they are still embracing and it has changed to a white tank top. (00:18:14)
Suggested correction: It's not for some weird reason. It follows the fade out with the title "more than enough" and it's meant to creatively signify the passage of time between the two embraces. The first embrace is after Mitch tells Slim that everything is going to be OK, even though he cheated on her. Then a notable amount of time has passed, both of them are dressed entirely differently, and with this turn of the second embrace Slim tells Mitch that she can smell Darcelle's perfume. So she now knows all his lies.
You are correct. Slim finds out about Darcelle. She smells the perfume on a different day - meaning that Mitch is still having affairs. She says "You're not going to talk your way out of it this time." So time has passed since she first caught Darcelle's page to Mitch.
Answer: Terrifyingly, it absolutely is not a stretch; abusers can lay the groundwork for a very long time, including years, before "revealing" themselves. The better to manipulate not only the victim, but the people around them, who will say "Oh, I've known him for years and he wouldn't do that" if the victim discloses abuse. As to your second question, you have to decide for yourself; abusers will often explain their actions as being motivated by love, but whether they believe it themselves or simply use it as a controlling tactic is a vexed question.
I believe that Slim was not abused at first because everything was going fine for Mitch. Slim was - as she later points out - taking care of his house and his child. She had not yet realised his deception. He was able to work, engage in affairs, then return to his nice home, with a beautiful wife and child. When Slim finally caught him and refused to tolerate his behavior, he was ready to "openly" abuse and control her.