FY, I went to tango classes years ago (when H was having his A). He didn't seem to care but I really enjoyed them for a while. In the end, I quit because I was having to dance with smelly men. At the time, H wouldn't have minded if I'd met someone. In fact, he says it would have been a relief. He showed zero interest in the fact that I was taking them but they helped me feel more confident and adventurous.
I'd certainly give it a go if I were you. You have nothing to lose.
Me: 51 H: 52 T: 23 yrs M: 19 yrs S18, D16, S14 (special needs) PA: 2003/2004 Piecing: 2004 on Suspect H had EA: 8/2012-12/2012