Do I consider myself a mistress?

I'm chatting a guy who has a girlfriend. We usually talk about general life and our problems. He thanked me that I didn't judge him when he feel vulnerable. Sometimes we call either other.

I feel sorry for this guy coz he don't feel safe talking about his problem to his girlfriend. I even encourage him to talk to her. To the communication thing.

I told my friends about this and they called me a mistress😔 I just want to help someone. I have no intention to steal him 😑
Do I consider myself a mistress?
Post Opinion