Letting staff go is often the most emotionally draining function a practice owner has to perform. There's just nothing enjoyable about it.
Here are two points that can help take the emotion out of it:
a. Staff members are the ones who decide whether they'll be dismissed or not by playing by the rules or not.
b. Most importantly, you have to do what is right for your patients, the rest of the staff, and yourself.
I guarantee you this: You will feel better once you get rid of an employee who you've lost confidence in.