As the world waits for a verdict in the trial of Sean "Diddy" Combs, testimony from women who say he physically and sexually assaulted them is at the heart of the prosecution's case.

       Jurors heard 13 days of testimony from three alleged victims who took the stand to help prosecutors build their case against Combs. Cassie Ventura, a singer and longtime girlfriend of Combs, and a former girlfriend who appeared under the pseudonym "Jane" both testified that Combs physically assaulted them and pressured them to participate in drug-fueled sex parties known as "freak-offs" or "hotel nights," and that they feared violence or reputational harm if they refused. A former Combs personal assistant, who testified under the pseudonym "Mia," told the jury that the rap mogul sexually assaulted her and also became violent with her and that she feared similar repercussions. Combs has denied all of the charges.

       Combs' defense countered that while some of the women may have come to regret their participation in the sexual encounters, they were willing participants at the time. Defense attorneys also told the jury that the women not only remained in personal and professional relationships with Combs afterward, they also professed affection and even love for him in messages that were shown to the court. His attorneys also argued in part that episodes of alleged domestic violence were driven by Combs' jealousy and drug addiction.

       After six weeks total of testimony, the jury now has the case as many observers grapple with one of the most difficult questions regarding allegedly abusive relationships: why didn't the alleged victims just leave?

       Prosecutors attempted to address the issue by presenting testimony from a psychologist who told the jury that many people opt to stay in abusive relationships often because they feel trapped or form an "intense psychological bond" that draws them to their abuser.

       Psychologists and experts in the field of domestic violence with whom ABC News spoke – none of whom had any connection to the Sean Combs case or its participants, nor were they asked to speculate about its testimony or outcome – said there are many reasons why people may feel unable to "just leave" abusive relationships.

       "People always ask, 'Well. why do people stay in an abusive relationship?' as if it's the victim's fault," Joanna Otero Cruz, executive director and president of Women Against Abuse, a non-profit domestic violence advocate and service provider based in Philadelphia, told ABC News. "The question should really be: why do abusers choose to hurt someone that they're supposed to love? How did the abuser prevent the other person from leaving?"

       Many survivors may not recognize that they're in an abusive relationship because the relationship didn't start off that way, experts said.

       "Perpetrators don't usually start off abusive," Carolyn West, a professor of clinical psychology at the University of Washington, told ABC News. "There's a grooming process oftentimes where they gain that victim's confidence before the abuse starts. And so they really present themselves as wonderful, caring partners."

       West, who studies the long-term consequences of intimate partner violence and sexual assault and who has testified as an expert witness in domestic violence cases, said perpetrators may psychologically manipulate their partners into thinking that they're overexaggerating the abuse being experienced. This can take the form of the perpetrator telling the survivor that they're being overly sensitive, that they're misunderstanding or misconstruing what happened, or telling their partner that the abuse is their fault. This may in turn make the survivor feel that they can behave in a way that can control the abusive partner, West told ABC News.

       "'Well, if I make dinner, or if I keep the kids quiet, or if I do this thing, if I'm attractive enough or wear more dresses, just whatever it is, then I can control the abuser's behavior,' which they can't," West said. "So, you're second-guessing yourself and not trusting your own perceptions."

       It takes an average of seven attempts for a person to leave an abusive relationship, according to the National Domestic Violence Hotline.

       The reasons are many, according to the experts with whom ABC News spoke. They include physical barriers that may prevent a survivor from leaving. A perpetrator may isolate a survivor from their friends and family, who don't know about the abuse. The abused partner also may feel ashamed or embarrassed about revealing that they experienced abuse. Additionally, family and friends may not support the survivor leaving, making them feel as if they have nowhere to turn.

       There may be financial barriers that prevent people from leaving as well. The survivor may not have a job, or may lack the education necessary to get a job so they can support themselves, according to experts. Leaving could also result in a divorce or a custody battle over children that could take many years to untangle.

       Hayat Bearat, a professor at Northeastern University School of Law and director of the school's Domestic Violence Institute, told ABC News that a couple also might have dissipated assets, or the abuse perpetrator may have moved all funds into an account over which they have sole control.

       "[The perpetrator] might put properties in other people's names or in business names and things like that," Bearat told ABC News. "So … the process of seeking what [the survivor is] legally entitled to becomes even more complicated without counsel."

       Additionally, an abusive partner may express remorse after a violent incident and promise they will change. The abused partner may then feel hopeful and so agree to forgive their abuser. Then there will be a period of calm before the abuse resumes. This repeating cycle of remorse, hope and abuse can become a barrier that prevents a person from leaving the relationship, according to Bearat.

       Survivors also may not want to leave because they feel that they've invested too much time and effort into keeping the relationship together to abandon it, Bearat added.

       "Oftentimes, they hang on to that hope of maybe the abuser will change and there's just such a slim chance of that ever happening without them taking accountability," Bearat said. "Most of the time it's very unlikely to change. But a survivor has that hope, and it's their hope to have and so I think it's their decision" if they want to leave.

       If the perpetrator is someone with a high profile, leaving can be even more difficult. The survivor may be fearful of leaving because they may be seen as less credible than their abuser, and the high-profile person may have money or power that they can use to control their abused partner, West said, including coercing them to remain in the relationship against their will.

       "That's how perpetrators operate. If they can keep you, test your boundaries, get you doing things that you don't feel good about, and then they can use that to further control you," West told ABC News.

       People who are experiencing domestic violence can call the National Domestic Violence Hotline at 1-800-799-SAFE (7233) or text BEGIN to 88788 for 24-hour confidential services. Survivors can also contact their state or local hotlines.

       Otero Cruz, from Women Against Abuse, said leaving an abusive relationship is the most dangerous time for survivors. She encourages anyone leaving or thinking of leaving to first call a domestic violence hotline and speak to a counselor, who can walk the survivor through a safety plan and measures that they can take to ensure that leaving won't escalate the abuse.

       The experts added that when survivors open up and confide in someone about the abuse – whether to a family member, a friend, loved one or other support system – it's important to listen without judgment and to not force the survivor into decisions they may not be ready to make.

       'We can provide affirmation. You know, 'I'm sorry that you're going through this, but you're not you're not alone,'" Otero Cruz said, as an example.

       "Being able to intervene very early, to talk to them about what healthy relationships are, would be a good start as well," according to West.

       West also said people should advocate for more funding for domestic violence and sexual assault services to help survivors amid potential budgetary cuts on the federal and state level.

       "We're getting too many cuts … so making sure that they're readily available, particularly in communities of color, queer communities, low-income communities, for young people," West said.