Telling my girlfriend another girl/women is crushing on me?

Anonymous
I need some opinion as to whether my girlfriend is right about being mad at me. This week I went to buy a Car for a friend of mine, we bought the car. The seller was a lady, who is married according to what she told me. I did all the talking so she has my number, it's been couple of days that she has been texting me , finding different reasons to text me. Yesterday she was flirting as well. So when I was talking to my girlfriend yesterday I told her about that lady that's trying to hit on me lol. And she got mad and stopped talking to me. She said there I am always trying to get with other girls and that she thinks I'm playing her. (She caught me couple of times flirting with other girls before. )but I really like her, she is super pretty and fun to be around. So do you think I should have never told her about that married lady?
Telling my girlfriend another girl/women is crushing on me?
14 Opinion