What should I do.?

So my husband told me that he needed to tell me something. And told me that he was so sorry but he texted a girl that he used to know (his side of the family no relation). And they were texting back and forth then she texted and said if he had ever thought about before when they first met if he felt like if he wanted to have sex. He said he did back then and she told him that it would have been different and this and that. And then he said he stopped texting her and she messaged back saying that if he wanted to be fuck bodies and she texted again saying it would be weird but if he wanted she could get some of her friends so he could have that. And he said no he didn’t want all of that and he said he didn’t text her all day till the next morning and told her it was all a mistake and that he shouldn’t have messaged her and told her bye and to not text him again and he blocked it and that was it… I really don’t know how I feel about this .. does Any one have any advice or just anything.. I’m just lost..