While men and women can be friends, it isn't always easy. A 2012 study published in the "Journal of Social and Personal Relationships" found that such relationships often carry the burden of unrequited attraction. With this in mind, it's important to establish firm and clear boundaries so your relationship doesn't cross the line from friendship to an uncomfortable or inappropriate situation.
A simple way to set the boundaries you need to keep a platonic friendship from becoming uncomfortable is to be clear about your intentions. If you genuinely want a buddy to go surfing with, but the girl you're friends with is secretly hoping you'll fall in love with her, the friendship is likely doomed. It's best to address the issues from the beginning and allow any elephants to exit the room. Be honest with yourself. If you find yourself struggling to repress sexual desires toward your friend, it will be difficult to maintain the boundaries you want.
Monitor Physical Behavior
Don't engage in physical behavior with your opposite-sex friend that you wouldn't with a friend of the same gender, warns psychologist Clifford N. Lazarus, Ph.D., in an October 2010 article in "Psychology Today." If you already have a romantic partner, a good gauge of whether a physical expression is appropriate is whether or not you would do it in front of your partner. In other words, if you wouldn't kiss your platonic guy friend on the cheek when your boyfriend is around, don't do it when he isn't. Overt physical affection is a fast way to blur the boundaries between friendship and romance.
Set Ground Rules
You need to set some ground rules if you want to maintain appropriate boundaries in your relationship, notes Orthodox Rabbi Shmuel "Shmuley" Boteach in an article on Oprah.com. For example, avoid late-night dinners, long drives and secret-telling. If you're in a relationship, make sure not to divulge information to your friend that wouldn't tell your partner, Boteach advises. He unequivacally states that friendship with an ex-lover is a no-no. In this case, the boundaries you are seeking to establish have already been crossed.
Include Your Partner
If you're romantically involved, include your partner in your outings with your platonic friend. Doing so will send the message that you enjoy his company, but are perfectly happy with your current romantic arrangements. This will hopefully squelch any unrequited feelings on your friend's part. Including your significant other also helps to keep your friendship on a fun level instead of on an inappropriately intimate one.