ladies I need your opinion

Ok so I've been happily married for a year and a half now & my ex boyfriend messaged me saying he had run up on my Insta page and was wondering how I was doin saying I deserve to be happy and all this but he said he wasn't trying to start anything ..do I write back being nice or no? I'm jus the type of person that feels bad! Crazy I know lol but he did cheat on me & give me chlamydia! So then I jus wanna bot right back to be a bitch but I'm way over that