When dealing with a partner, the consequences of a substance abuse problem generally fall into psychological (and resultant behavior) and economic categories. Money, for example, can be diverted away from savings and joint interests, and toward fueling a habit. Psychologically (and behaviorally), a partner could be on the receiving end of mood swings, reduced sexual interest and functioning, lack of engagement from their loved one, and other forms of emotional neglect. They may also be coerced into becoming complicit in their partner’s addiction, being manipulated into covering for them or even providing them drugs, all under the guise of doing the actions out of love (or a promise that the addicted partner will seek help or treatment after this one last act).
A substance abuse problem is insidious. It creeps and sneaks its way into a user’s life: a drink to take the edge off a bad day becomes a drink just to make it through the day; a puff of a marijuana joint while hanging out with friends becomes any excuse to light up and get high.The same is true when addiction issues arise in relationships. A drug or drinking problem changes the way a user thinks and perceives the world around him, making him redirect all his attention, energy and focus into satisfying the need for more. This will also affect the dynamics of the relationship with the user’s partner: he becomes less a romantic or sexual companion and more a tool to further the addiction, a vessel by which the next high can be obtained.
In the words of a PsychCentral blog, “behavior reinforces the addiction.” Everything the patient does, whether or not he is aware of it, is to keep the fires of his vice burning. How he interacts with his spouse or partner becomes a piece of that machinery. The partner’s reaction can determine a number of other factors: if she offers an ultimatum, for example, that could be the end of the relationship, but it could also be the impetus for the user to go clean; if she becomes complicit in the addiction, it could spread the disease into more social circles.
Human sexuality is a very complex subject on its own terms, and throwing an addiction problem into the mix can have very long-term consequences. A 2013 study conducted by the University of Grenada found that male drug addicts remained sexually impotent even after going through rehabilitation. The study looked at the sexual performance of a group of 605 men, 550 of whom had been diagnosed with a substance abuse problem. The results, published in the Journal of Sexual Medicine, found that sexual climax was impaired long-term as a result of the consumption of cocaine, heroin and alcohol, the last of which is the drug that has the most effect on the ability of a man to achieve an erection.
As a stimulant, cocaine temporarily increases sex drive and the chances of engaging in promiscuous or risky sexual behavior. It also impairs or delays orgasm and leads to what the University of California, Santa Barbara calls a “massive decline” in interest in having sex and being able to perform sexually, in both men and women. There is the possibility that a cocaine addict might continue to abuse cocaine for the short-term boost in libido, completely unaware that the resultant decline in sexual performance is also due to the cocaine.The element of promiscuous sexual activity induced by stimulants such as cocaine and methamphetamine can also cause multiple difficulties, both within and without a relationship: sexually-transmitted diseases, unwanted pregnancies, abuse and neglect of sexual partners, depression, and a gradual decline of effort and interest in pursuing long-term and serious relationships.),
Erectile dysfunction (with or without the presence of prescription or recreational drug abuse) can have a devastating psychological impact on the partners in a relationship. The Journal of Urology interviewed 168 men with ED and found that those who reported that their sexual impotence had any psychological impact on their life also reported higher rates of depression and anxiety, as well as diminished belief in their functional status and sexual confidence.
Sexuality is one of the many components of a relationship, and how it is impacted by substance abuse could also play a role in how the other components of the relationship play out. As intimacy and trust levels are impacted by dwindling sexual capacity and increased periods of depression and turbulent mood swings (caused by withdrawal and comedown effects), the chances of emotional and physical abuse among partners increases. That was the conclusion reached by researchers writing in the American Journal of Orthopsychiatry. In 2011, they interviewed 106 fathers who were receiving treatment for a methadone addiction and found that men who were dependent on such opioids were more aggressive physically, sexually and psychologically toward their partners, than men who were in a control group.
Perhaps for women more so than men, the intersection between addiction issues and issues of intimacy may be borne from trauma suffered during childhood. In the words of TIME magazine, “the vast majority” of people who struggle with a substance abuse problem have also suffered major trauma in their past. And researchers writing in the Journal of Psychiatric Research claim that women who have suffered a traumatic event in their lives are more conditioned to feel fear than men, which may manifest as fears of loneliness and abandonment that they attempt to self-medicate with drugs and alcohol (in contrast to men, who generally introduce prescription and recreational drugs into their relationship dynamic for improved sexual performance).
Outright preventing an addiction may be impossible, but an observant partner will notice if his companion is exhibiting signs of substance abuse:
If there is enough cause to suspect a substance abuse problem, the partner should ask his companion quickly and directly, without a tone of confrontation or judgment. Doing so will give the user an opportunity to come clean, while she still has some say in the matter. From this foundation, professional treatment and counseling can be sought to repair the damage done, and help both partners bridge the gap that addiction tried to carve into their relationship.
 “When Substance Abuse and Intimacy Issues Are Linked.” (August 2013). Psych Central. Accessed April 14, 2015.
 “Beta Blockers and Other Drugs That May Cause Erectile Dysfunction.” (March 2014). Healthline. Accessed April 14, 2015.
 “Recreational Use of Erectile Dysfunction Medications in Undergraduate Men in the United States: Characteristics and Associated Risk Factors.” (2011). Archives of Sexual Behavior. Accessed April 14, 2015.
 “Drug Abuse Impairs Sexual Performance in Men Even After Rehabilitation.” (January 2013). Science Daily. Accessed April 15, 2015.
 “Psychological Impact of Erectile Dysfunction: Validation of a New Health Quality of Life Measure for Patients With Erectile Dysfunction.” (November 2002). Journal of Urology. Accessed April 15, 2015.
 “Drug Abuse and Intimate Partner Violence: A Comparative Study of Opioid Dependent Fathers.” (April 2011). American Journal of Orthopsychiatry. Accessed April 15, 2015.
 “How PTSD and Addiction Can Safely Be Treated Together.” (August 2012). TIME. Accessed February 20, 2015.
 “Sex Differences in Fear Conditioning in Posttraumatic Stress Disorder.” (January 2013). Journal of Psychiatric Research. Accessed February 20, 2015.
 “Why Drug Addicts Will Always Choose Drugs Over Love.” (June 2014). Psych Central. Accessed April 15, 2015.