Whether you know that your BFF's new beau is a total player, you see them constantly squabble or you think their interests seem beyond mismatched, helping a friend to realize that her guy is wrong for her is a challenge that you may need to step up to. Telling your friend something that she doesn't want to hear is is hardly the best part of your relationship -- but in the long run, she'll appreciate the care and consideration you are showing her.

Staying Sincere

Think about how you would feel if your friend was preaching at you, telling you that you're wrong or that your guy isn't all that you think he is. Most likely, you wouldn't get a warm and fuzzy feeling from this not-so-subtle tactic. Instead of approaching your friend in a preachy, better-than-her way, act sincere. Just as you would want to genuinely show how sorry you were when apologizing, telling a friend something that she might not want to hear requires the same level of sincerity, according to the experts at the TeensHealth website. If you tell her, "I would never date your guy. He's just not cute enough for me," you'll come off sounding judgmental and insincere about your intent to help her realize that he's just not right for her.

Take the Blinders Off

It's common, according to the experts at the TeensHealth website, for young adults to have blinders on when it comes to what their romantic partner is really like. If your friend isn't seeing her guy for who he really is, helping her to realize the truth is a must. While this may bring up hurtful feelings or leave your BFF sad, she needs to know if the reality of her guy isn't meeting the fantasy in her head. For example, if she truly believes that her so-called past-player beau has changed his ways -- and you know for fact that he's still seeing other girls -- tell your friend that her image of him isn't so. Don't beat around the bush or simply hint at what you know. Use an honest approach and tell her exactly who this guy is and how you know it.

Rationalizing Respect

Without mutual respect, a relationship isn't likely to last for the long run. Accepting a romantic partner's beliefs, boundaries and opinions shows a level of respect that is necessary in a healthy relationship, according to the National Campaign to Prevent Teen and Unplanned Pregnancy's Stayteen.org website. If you're tired of seeing the disrespect that your friend's guy heaps on her, you need to step in and show her just how wrong he is. Your friend might not fully realize that her guy isn't respecting her or puts down her decisions. Show her the light by pointing out the exact times when he acts disrespectful. For example, the three of you are choosing an activity to do on a weekend day, your friend suggests ice skating and her boyfriend responds, "No way. Your ideas are always so stupid," it's time to jump in. Ask your friend if she thinks it's acceptable for her guy to talk to her like that.

Uncomfortable Situation

If your friend shows obvious discomfort or acts uneasy around her guy, it's likely that he isn't right for her. While some degree of nervousness is normal for teens and young adults who are in new relationships, constant feelings of being uncomfortable may signal that your friend wants a boyfriend more than this specific boyfriend. Your friend's negative or uncomfortable feelings are a sign that her guy isn't the right one for her, according to the professionals at the Palo Alto Medical Foundation. Ask her what she likes about him or what interests they share. If she can't come up with an answer, talk to her about the possibility that she just wants a relationship, regardless of who the guy is.