My ex-girlfriend and I stayed friends months after our break up. I know some people would really raise eyebrows on this arrangement but that’s what we agreed on. We talk from time to time but it’s mostly about neutral stuff, nothing about us anymore. Last week she messaged me asking if it’s true that I joined this Latin America singles club thing. She said a friend told her about it but wouldn’t drop a name. I noticed that she was acting all jealous about it. Although she said that she was happy for me, I could see in her messages that she was actually feeling something negative about it. Trust me, I’ve mastered reading her emotions behind her messages. How should I react about this?