You need to be a little more honest with yourself.
Here are some of the places you haven’t been truthful:
* You’ve written that the girl he was sexting with was someone he’s never met before — and then in the same sentence you say that they used to talk in the past — and then in the present. While he may never have met her in person, they have had a long term relationship that served some purpose. 😳 If he wanted a more anonymous sexual experience, he could have gone to Playboy magazines. But nurturing a relationship with this sexting partner is different.
*Then you say that you know it didn’t mean anything — but your behavior indicates that clearly it did mean something to you! 😕 If it truly didn’t mean anything, you wouldn’t have retaliated by doing the same thing he did, knowing how much it hurt you when he did it. 🙁
* You say that you forgave him, but it’s wildly clear you didn’t. You’re still angry and upset about what happened which is why you acted out and did what he did.
* The fact that he hadn’t been forthcoming with the relationship is something you didn’t address. He was keeping this relationship with his sexting partner secret from you. Again, this isn’t a stash of Playboy magazines under the mattress. It’s a relationship.
Talking it over and forgiving him were leaps of faith on your part, but judging by your behavior, I don’t think you’ve forgiven him just yet. Slow down and consider what’s REALLY been going on between the two of you.