Over the course of 10 years I've had lovely people come to my e-mail marketing software company VerticalResponse, and sadly they've 'broken up with us' for various reasons. We all have them, those special people in our lives that 'got away.' It happens in our love lives just like our business lives and it sucks but let's face it, it's just going to happen. Some people might not like the path they're on (i.e. the alter), some don't like their boss (their significant other), some hate the job they do (the dishes!), so, they leave. If you're lucky, they leave on great terms (I once got an ex to be an investor) and you're fortunate enough to keep in touch with as many of them as you can.
I've got my own people that got away; Johann an engineer who is an amazing colleague. I'll always be a reference for him and I'll always go to him with my engineering questions and he'll be there. I've got a Keisha, who was too smart for what we hired her for and if she ever contacts me about anything she needs, I'll be there. Then there was Brittany, who hated her boss but loved our company and our customers. But when she thought about the person she had to report to each day, she chose another company. (Her boss, for various reasons, no longer works for us.)
Then there are those really angry folks who leave on bad terms. Perhaps they left before their bonus was handed out but felt entitled to it anyway. Or maybe they were about to be fired for non-performance but saw the writing on the wall and left beforehand. They probably harbor some serious resentment for not only you but for your business as well.
What do you do about it and how do you control it? The short answer is, you don't. But here are a few things to think about when and if this happens.
Every business is going to have one or more of these people. Don't take it personally! Just do what you do to be successful, focus on the employees and exes who matter, and forget about those exes who don't - in life and in business!