Ending a relationship is at best uncomfortable and at worst extremely painful, and the inability for text to convey tone can exacerbate any hurt feelings.

"Breaking up with text should be avoided unless the relationship has become unsafe," says Thema Bryant, the former president of the American Psychological Association. Bryant is a professor of psychology at Pepperdine University and did her postdoctoral training at Harvard Medical Center.

To prepare yourself for the in-person conversation, you need to have a clear vision of how you want the talk to end.

"Have clarity about what you want to say and what outcome you're hoping for," Bryant says. "Prepare yourself for the different ways they may respond — surprised, angry, desperate, shut down."

You want to stick to your message but also communicate empathy and respect. Here's how to do that, according to relationship experts.

What to say

Start the conversation on a firm note. Bryant offers the following script:

"I would like to share how I'm feeling and thinking about us and then I would like to hear from you if there's anything you want to share. This is challenging so it would help if you let me get through my thoughts without interrupting and I will do the same when you're sharing."

It might be tempting to invent excuses that you feel might be less hurtful to your partner, but, even though well-meaning, this can end up being insulting or outright confusing.

This is a time for full transparency, says Lisa Marie Bobby, a psychologist and founder of Growing Self Counseling & Coaching. 

"An expression of true love and caring is to have an authentic conversation about what is going on inside of you that has led you to come to this conclusion," Bobby says. "Avoid the trite excuses."

How to say it

The tone of the conversation can be as important as the content.

"You want to determine and then communicate if you are clear you want to end it and will not debate it or if you're wondering if you all should end it and want the two of you to figure it out," Bryant says. "Those are very different tones so decide on which one you want."

If you're confident the relationship needs to end, it's fair to convey whichever emotion — anger, disappointment, resentment — that you feel. If you believe there is chance of reconciliation, perhaps be more discerning about which words you choose.

One of the biggest mistakes people make during a breakup is "saying cruel things and later wanting the person back but your words have caused real harm," Bryant says.

If done right, these talks don't have to be total character assassinations. In fact, they can end up being helpful to the other person.

"In these conversations the other person may have the opportunity to absorb some feedback or insights about themselves that will help them grow and develop," Bobby says.

Want to be a successful, confident communicator? Take CNBC's new online course Become an Effective Communicator: Master Public Speaking. We'll teach you how to speak clearly and confidently, calm your nerves, what to say and not say, and body language techniques to make a great first impression. Sign up today and use code EARLYBIRD for an introductory discount of 30% off through July 10, 2024.

Plus, sign up for CNBC Make It's newsletter to get tips and tricks for success at work, with money and in life.