Would you respond to an ex's text if you are married?

Stephie
So I went out for my best friends bday and saw my ex, he tapped me on shoulder and said hi knowing my husband was there. My husband didn't see it was very fast. Then later at like at 3am he texts me "Saw you tonight" and then again an hour later through Facebook. I have ignored his previous texts before so if I respond in a friendly manner he will still know I have that number. He knows it's my Facebook because he congratulated me when I got married. Now I am a nice person and know how it feels to ignore someone but I was hurt by this guy. And I am not his friend. So would you agree that there is no point in responding? I am happy with my husband and don't want my husband to somehow find out and think bad of me either. Why do you think he text me the same thing twice in different ways? Like what does he want out of this? For me to flirt w/ him knowing I am married? Like I don't get the point of him doing that? Lol and before years ago when I wanted to get back I tried and tried and he said no so I moved on and found my true love there and am super happy now and we have our blessing on the way and now why is he trying, he had his chance. Anyone gone through this? Thoughts? Advise?