Having a "friends with benefits" relationship has become almost commonplace in today's society.

It's a way to express your desires without any strings attached (sometimes). You already get along so well as friends, so why not engage in something that’s mutually satisfying and fun for the both of you, right?

This concept may send your sweet old grandma running to the church to send some prayers your way because it's rather taboo to many people. 

A relationship is often viewed as something meant to be committed and monogamous. One person meets another, sparks fly, romance blossoms, and wedding bells are audible in the distance.

But times have changed, and not everyone is getting some this way anymore. (Sorry, grandma.)

Those who are not in support of the whole "friends with benefits" thing do have a point about how friends with benefits usually ends. There are pros and cons to having a friend with benefits, but it seems the negatives may outweigh the positive aspects that exist. 

A lot of people would warn you against pursuing this because someone usually gets hurt. It's never the intention on either end for somebody to take a hit, but it's hard to avoid.

Why do FWB relationships end? 

Friends with benefits relationships usually end when one person catches feelings that aren't reciprocated. But other reasons can include a lack of respect or boundaries, waning interest in the fling, or another opportunity coming along for a serious relationship.

It can be almost impossible not to get personal feelings entangled when getting intimate with another person, even if it was established from the start that the relationship would be strictly physical. 

A big part of intimacy is mental because you have to at least be attracted to the other person and enjoy their company in order to have a good experience. So, when emotions and attraction get mixed in the same pot, things get messy.

But psychotherapist Paula Kirsch explains that FWB relationships actually have worked out well for some young women, saying, "I have heard more than one twenty-something female client report benefiting from being friends with benefits. They often say that they previously have only had unsatisfying, awkward, bad, or coerced sex. Finding a trusted friend that they were comfortable with opening up an opportunity for them to explore their sexuality and sometimes even find healing."

For some people, the arrangement works perfectly; for others, the spark fades. One person may enter into a casual relationship in the hopes of taking things to the next level over time. But not only is this not guaranteed, but if and when the relationship doesn't head in that direction, there can be serious casualties to the friendship.

What prevents FWB relationships from turning into real relationships?

Is it impossible to turn mutual physical satisfaction into a full-blown partnership? People do it, but it's pretty uncommon. Try as you may to deny it, this is a simple fact, but is it really that simple? 

There are some signs that you can look for like possibly an increased case of communication from either texting or calling. 

According to the director of clinical research programs at Felnett Health Research Foundation, Damian J. Sendler, Ph.D, if the rate at which you've been getting text messages from your fling started to increase, that's a signal that you could be moving towards a real relationship. Communication is key. 

Another important indicator of a possible transition into a real relationship is if the two of you actually spend time together besides hooking up. Hanging out outside of just having sex is a big sign that your friend genuinely enjoys your company, and not just for sex. 

Counselor and therapist Audrey Tait says there are a few reasons why a FWB relationship can't turn into a real relationship: "Friends with benefits may be prevented from becoming a real relationship if one of the persons is already in a committed relationship or is not interested in committing to a relationship."

If you feel deeply for this person and are getting intimate emotionally, that could be another sign that this is more than just a casual thing. The two of you maybe are sharing each other's feelings without knowing it, including knowing about one another's lives, friends and family.

According to Kirsch, if you have a friends with benefits partner that you can trust and open up to over time, there might be some hope for it to turn into a real relationship. "[Some of my clients] were able to figure out what felt good and what worked for them sexually. It may be that they learned to relax. These relationships seem to run their natural course, ending with life transitions. I've seen one or two evolve into actual lasting relationships," she said.