I personally don't believe infidelity EA or PA means the death of a marriage but your H is very young. You're young too but you're a mom and with that comes some maturity. My concern isn't the grass is greener mentality or the FOO. Every LBS here has had to fight those battles. My concern is that it's almost a knee jerk reaction to cheat when he's unhappy. A marriage can't survive that. You can't live like that long term. I trust you know what you want. And that there is good here. And enough good to want to try to make it work. But strongly suggest reading some threads from beginning to end to see what this process of standing looks like. Especially with a person who struggles so deeply with fidelity.
I also need you to understand that while you most certainly could've handle things better in your relationship. That you've brought in bad habits and trauma responses. All of the things we need to own. His repeated infidelity means you are allowed to have enormous trust issues. And that he isn't entitled to privacy. The normal rules of relationships don't apply to serial cheaters. Own what's yours. Don't carry your H's baggage. That's his to handle.
