Skip to main content

Verified by Psychology Today


When Are Opposite Sex Friends a Threat to Your Relationship?

Six things you should never do when you have opposite sex friends.

Istockphoto w/permission
Source: Istockphoto w/permission

Can men and women be just friends? Despite the fact that opposite-sex friends have become more common in the past several decades, it’s a situation recent research shows most people view with suspicion1 and these suspicions are actually substantiated by research.

For example, Monsour, Harris, and Kurzweil2 found that 64% of men and 44% of women reported that their cross-sex friends became their sexual partners. However, as men and women have more opportunities to interact with one another in workplace and social settings, it is inevitable that people of the opposite sex will find common interest and connection with one another that is likely to evolve into friendship.

These relationships don’t generally pose problems unless one or both parties in the friendship are in an exclusive intimate relationship with someone else. When this is the case, decades worth of psychological research shows, if not handled properly, there is strong potential for the opposite sex friendship to become a threat to the intimate relationship.3-19

What defines an exclusive intimate relationship isn’t just sex, it’s an emotionally intimate bond that allows for trust and vulnerability between two people. Creating an intimate bond with someone requires making them feel safe, loved, and cared for in a way that prioritizes your relationship with them above other relationships. The paradox of the intimate bond is that when it is treated with the care you would give if it were fragile, then it becomes stronger.

Breaking that bond doesn’t require a sexual act with someone else. It can be broken by creating a bond with someone else that interferes with the trusting intimate bond you have with your partner. That’s why it is widely recognized that affairs can be physical, emotional, or both.

While the person in the intimate relationship holds the greatest responsibility for protecting it, both members of the opposite sex friendship can threaten the bond in an intimate relationship.

It is not uncommon for the opposite sex friend to be jealous of the intimate relationship and/or engage in inappropriate behavior that is disrespectful of the relationship. One way this is done: when the friend crosses normative relationship boundaries and starts acting like the girlfriend.

For example, let's say a woman called Ashley asks her male friend who is in an intimate relationship with another woman to play golf on the weekend with her father, or she invites her male friend out for one-on-one drinks while she knows her male friend’s partner is out of town visiting family, or she inappropriately flirts and touches her friend in front of her friend’s intimate partner.

When someone you have an intimate relationship with objects to an opposite-sex friendship, it is a mistake to assume that this is jealousy stemming from insecurity. Partners with high self-esteem will not tolerate poorly handled opposite-sex friendships. This is usually a sign of their emotional intelligence and their understanding of what is required to maintain an intimate bond. Translation—the problem very likely isn’t the partner who is objecting, it is very likely the way the opposite sex friendship is being handled by one or both of the friends.

Below are some guidelines for preventing your opposite-sex friendships from becoming toxic and damaging your intimate relationship.

1. Never prioritize an opposite-sex friend above your intimate relationship. Telling an intimate partner that if he/she doesn’t accept your opposite-sex friendship that you will break-up with them, is lethal to the intimate relationship, and akin to the emotional abuse used by narcissistic individuals when they engage in the abuse tactic of triangulation.

2. Don’t hide activities with your friend from your intimate partner. Lies of omission are lies, and when you start hiding your behavior from your partner you are engaging in a form of deception that is aimed at controlling your partner’s perception. Once you have made the choice to hide your behavior you are already keenly aware that what you are doing is likely to harm the relationship. This type of behavior directly kills any bond of trust. If you take a weekend trip out of town with your opposite-sex friend and neglect to tell your partner that your friend is with you, that threatening behavior to the bond you have with your partner.

3. Don’t insist that your partner also be friends with your opposite-sex friend. Your intimate partner has a right to choose who he/she wants to be friends with. If your partner doesn’t want to spend time with your opposite-sex friend don’t try to force this on them or it will likely backfire.

4. Don’t engage in flirtatious behavior with your friend in front of your intimate partner. Touching your opposite-sex friend in a way that would generally be considered flirting behavior between two people who are sexually attracted to one another or making jokes of a sexual nature is akin to emotional abuse. For example, if your friend is laughing and leaning in to touch your arm or leg in an intimate way and you respond accordingly in front of a group of other people, you are creating a situation that is humiliating for your partner to be in.

5. Don’t form inappropriate opposite-sex friendships. If you are a 60-year-old man regularly texting and hanging out with a 30-year-old single woman that you are obviously attracted to, and calling this a “friendship,” the chances that your intimate partner will not find this disrespectful of your relationship is almost zero. Use the reasonable person test, if a reasonable person looking from the outside would question the relationship or think it was odd, then it is almost guaranteed that your partner will too. If you wouldn’t like your partner doing it to you, don’t do it to your partner.

6. Don’t call your intimate partner jealous or crazy. If your behavior with your opposite-sex friend is being perceived by your partner as a threat to your intimate bond, then accept it for being exactly that. It is not just your partner’s problem to deal with. The intimate bond you have with your partner is being created between the two of you. If this bond is meaningful and worthwhile to you, then you must protect it. Sometimes protecting your relationship means giving up some of your own personal freedom or choice so that you build something that is greater than the sum of its parts. If you are unwilling to do this, then perhaps you aren't ready for the relationship.

Facebook image: Just dance/Shutterstock


1. Gilchrist-Petty, E., & Bennett, L. (2019). Cross-Sex Best Friendships and the Experience and Expression of Jealousy within Romantic Relationships. Journal of Relationships Research, 10, E18. doi:10.1017/jrr.2019.16

2. Monsour, M., Harris, B., Kurzweil, N. et al. Sex Roles (1994) 31: 55.

3. Afifi, W. A., & Faulkner, S. L. (2000). On being ‘just friends’: The frequency and impact of sexual activity in cross-sex friendships. Journal of Social and Personal Relationships, 17, 205-222.

4. Afifi, W. A., & Burgoon, J. K. (1998). ‘We never talk about that’: A comparison of cross-sex friendships and dating relationships on uncertainty and topic avoidance. Personal Relationships, 5, 255-272.

5. Bleske, A. L., & Buss, D. M. (2000). Can men and women be just friends? Personal Relationships, 7, 131-151.

6. Bleske-Rechek, A., Somers, E., Micke, C., Erickson, L., Matteson, L., Stocco, C., Schumacher, B., Ritchie, L. (2012). Benefit or burden? Attraction in cross-sex friendship. Journal of Social and Personal Relationships, 29, 5, 569-596.

7. Hartup, W. W. (1975). The origins of friendships. In M. Lewis & L. A. Rosenblum (Eds.), Friendship and peer relations (pp. 11-26). New York, NY: John Wiley.

8. Hays, R. B. (1988). Friendship. Handbook of personal relationships: Theory, research, and interventions (pp. 391-408). New York, NY: John Wiley.

9. Kaplan, D. L., & Keys, C. B. (1997). Sex and relationship variables as predictors of sexual attraction in cross-sex platonic friendships between young heterosexual adults. Journal of Social and Personal Relationships, 14, 191-206.

10. Monsour, M. (1992). Meanings of intimacy in cross- and same-sex friendships. Journal of Social and Personal Relationships, 9, 277-295.

11. Monsour, M. (1997). Communication and cross-sex friendships across the life cycle: A review of the literature. In B. R. Burleson & A. W. Kunkel (Eds.), Communication yearbook 20 (pp. 375-414). Thousand Oaks, CA: Sage.

12. Monsour, M. (2002). Women and men as friends: Relationships across the life span in the 21st century. Mahwah, NJ: Lawrence Erlbaum.

13. O’Meara, J. D. (1989). Cross-sex friendships: Four basic challenges of an ignored relationship. Sex Roles, 21, 525-543.

14. Rawlins, W. K. (1992). Friendship matters: Communication, dialects, and the life course. New Brunswick, NJ: Transaction Publishers.

15. Reeder, H. M. (2000). ‘I like you ... as a friend’: The role of attraction in cross-sex friendships. Journal of Social and Personal Relationships, 17, 329-348.

16. Swain, S. (1992). Men’s friendships with women: Intimacy, sexual boundaries, and the informant role. In P. Nardi (Ed.), Men’s friendships (pp. 153-171). Thousand Oaks, CA: Sage.

17. Werking, K. (1997). We’re just good friends: Men and women in nonromantic relationships. New York, NY: The Guilford Press.

18. Wright, P. H. (1984). Self-referent motivation and the intrinsic quality of friendship. Journal of Social and Personal Relationships, 1, 115-130.

19. Carter, Z. A. (2016). Married and previously married men and women's perceptions of communication on facebook with the opposite sex: How communicating through facebook can be damaging to marriages. Journal of Divorce and Remarriage, 57, 1, 36-55.

More from Jennice Vilhauer Ph.D.
More from Psychology Today