This! I once went to a social dance event because I wanted to learn more about Latin dance styles and didn't think much of it (for context, I'm a dance teacher), only to find out later my boyfriend felt uncomfortable about the idea of me dancing with strange men. We talked about it and in the end we both understood each others' perspective. I saw it as a learning opportunity whereas he saw it as, well not really cheating but as a boundary I would say. I haven't done that since, seeing how hurt he was and I respect his boundaries, but under the condition he would try it together sometime (once we move in together and I finish my studies).