Long read.. Sorry I’m advance.

So my husband said something I couldn’t even believe last night.. We were spending some time asking each other questions from the card game “Table Topics - Couples” just to connect and have some conversations. Backstory - my husband cheated on me (apparently in a moment of weakness) in the beginning of our marriage. He was sexting and got nudes from his ex, apparently only one time. I was pregnant and our sex life was nonexistent at the time and that caused him to make some bad decisions I guess (even though he said that doesn’t excuse his actions - which it 100% doesn’t) he begged for forgiveness, apologize and promised to earn my trust back. Previous to that happening our relationship was perfect, been best friends since high school and our marriage had been a fairytale. It took a lot to forgive him and try to move past it because my ex cheated on me, was abusive and the whole relationship was so traumatic. He knows this and promised me from the beginning of our relationship he would never hurt me like that. Would never lay an unloving hand on me, would never cheat on me, etc. because I’m the women of his dreams and he’s been trying to win me over ever since we were freshman in high school. Back to last night, some how the topic came up of past relationships (from the question on the card) and it had to do with learning a lesson or something of that nature. I tried to move on because that was his only “relationship” before me and I didn’t want to relive that. Well he makes a comment and I said that I didn’t want to bring up him cheating and tried to leave it at that because it breaks my heart to relive those moments of our marriage. THEN he says “but was it realllyyyy cheating?” Or something along those lines. I was in total shock. I just stared at him.. I said “excuse me?” Thinking that I heard him wrong. (Spoiler: I didn’t, he really said that!) I said “yes, getting nudes from and sexting your ex while your married is 100% cheating” and he said “oh my god are we going to fight now” and I said “no, no we aren’t” and started to tend to our newborn and tried to pretend like that didn’t happen because I was just in shock and heartbroken that those words came out of his mouth. I trusted him 120% before him cheating and it really effected our marriage. Obviously. So many thoughts raced through my head while I laid there feeding our baby.. if he doesn’t consider it cheating in his heart, would he do it again? It took everything in me to work things out (because I don’t believe in divorce & he was so remorseful) and he should be thankful I stayed to work things out! I have self doubt a lot of the time but I’m an amazing wife, an amazing mother, I sacrificed so much (willingly) for my husband, my kids, our family and I would do it all again because that’s what a selfless mother and wife does.. but that comment was a slap in the face. It seriously ripped my heart out of my chest and I was left out of breathe. He ended up sleeping on the couch but today is acting super sweet and like everything is fine. I’ve carried on like it’s a normal day but I can’t get the conversation put of my head. Just because he didn’t fuck her, doesn’t mean he didn’t cheat. Does he truly not see that? Because I know of the roles were reversed, he would 100% consider it cheating. Can someone give me some advice? (Level headed advice)