Ask Amy: I know she was in my office when I wasn’t there

Dear Amy: I am a physical therapist, and I work in a building with others in the same profession.

I have my own office space. I used to rent it to a friend, who recently moved to another space on my floor when a room opened up.

After she moved, she asked to use my room for an hour when she knew I wouldn’t be there. I said yes.

Today when I came in, I noticed that she had been in my room after I left yesterday but hadn’t asked me first.

We are friends and I want to stay on good terms.