So, been happily married with my wonderful husband for nearly 2 years. Suddenly, my ex and I got started to chat (nothing serious like jogging considering we live close by or going out to lunch, he's also married) but this is like the second time he asks me to hang out with him... I honestly don't feel comfortable... I've talked to my exes before and they're also married, but I feel comfortable to do double date things instead.

What is a gentle and respectful way to say no thank you?

Thanks!!!