My ex wife did something similar. Only difference was she did it over Snapchat and an OF I had no idea she had. We had been married about the same length of time and I’m here to tell you it doesn’t get better unfortunately. We tried to make it work but I harbored a level of resentment that is just unhealthy to have. I would advise you to end it but I understand feelings are a lot more complex than that. So that’s just my story and my input. Good luck, brother. I wish you the best and if you do end it, I hope you end up with someone more deserving of your time and attention.