Employee problems

I am the boss at work . I have 2 employees that work with me. One is a receptionist and the other is my assistant. The receptionist, Mathis and I have worked together for 7 yrs. we have a personal relationship outside of work and I consider her my friend.

Brandy my assistant has had problems with Mathis. She says she is rude and condescending. I have never witnessed this behavior. Brandy’s husband was diagnosed with cancer recently and as you can imagine she has been super stressed . She has missed a lot of work, understandably.

Today, Brandy said she had had enough when Mathis brought 3 items to her attention. This was work that was incorrect, 1 quantity and 2 duration of use. Brandy , said she would not stand to be treated like this any longer. Another coworker encouraged her not to walk out and took her to the office managers office.

The office manager called me to her office. Said the situation had become unbearable for Brandy and that she was finding her another position for now. The office manager sided with Brandy. I asked that she speak with Mathis and get her side of the story .

I believe them both. I do feel that Brandy is super sensitive but also believe that Mathis is misunderstood by people that don’t take the time to get to know her. I feel bad. I am nervous and anxious . I have done nothing wrong. How to I feel better?