"If you love someone, let them go."

We usually think about that old expression when a relationship falls apart. But it also springs to mind for me whenever I'm involved in a different kind of breakup: when a great employee decides to leave the company.

lt can be hard to accept, especially when it's an A-player or a good friend giving their two weeks' notice, but it's a reality of business. In fact, the average person will have 10 different jobs before they're 40, and that number is only going to increase as more millennials join the workforce. For this cohort, job-hopping is the new normal.

Given those stats, it's probably best for you and your team to learn how to cope when a rock star employee moves on. Here's how we make sure that saying goodbye isn't painful.

Don't drag it out

Your gut reaction may be to promise an all-star employee whatever they want to get them to stay. But even if they accept your offer, it rarely works out long term. Once we had a great PR person hand in her resignation, saying she wanted more responsibility. Ultimately, we convinced her to stay by offering her a promotion. But a few months later, we found ourselves having the same discussion with her, and ultimately she left.

You may not be married to your employees, but your relationship is still a partnership: if one side isn't happy -- for whatever reason -- they're going to leave. Fighting this reality only delays the inevitable and complicates the separation.

Leave things on good terms

It can be an unpleasant shock -- or even hurtful -- to hear that an employee you deeply value has decided to leave. However, a dramatic or negative reaction will only harm your reputation and integrity in the long run.

And it's worth remembering that goodbyes aren't always final. John Lasseter left Disney only to find himself working there again after Pixar was acquired by the company. Steve Jobs left Apple in 1985 and returned in 1997 as CEO. We've had plenty of employees return to the company after stints elsewhere, like Jerry, our VP of People. Jerry took a great opportunity at fashion brand Aritzia and returned to O2E Brands a few years later, drawn back by our company culture.

When you keep the vibe positive and supportive -- wishing departing employees the best and even offering references or support with the new gig -- you keep the door open for great team members to come back.

Have a contingency plan

Practically speaking, the smoothest way to deal with losing an employee is to always be prepared for a worst-case scenario. We have a backup for every position in the office, working proactively with team leaders to ensure that everyone has a clear "successor." It means that even if someone leaves out of the blue, we're covered -- without interrupting deliverables.

At the same time, this policy lets us extend leadership training and development opportunities throughout the organization. "Successors" are often called on to step in for team leads during vacations. This enables managers to truly disconnect and "go dark" during their holidays while giving other team members valuable leadership experience.

It's always hard to part with a great employee, but you can't live in fear. All you can do is ensure your company treats people well, champions a culture of transparency, and tries to catch issues before things get too bad.

Ultimately, team members have their own lives to lead and career paths to follow. Some will stay. Some will leave. Some will even leave and come back. Amid this uncertainty, there's only one real measure of success: making sure you use the time you do have to learn and grow -- together.