This has rocked my world

Last January I found out that my wife of 35 years had been sexting a former colleague. I accidentally found out when she got a text and I went to take her phone to her. That’s when I saw the texts. They were extremely graphic. She told me it had been going on for about 3 months and wasn’t more than 3-4 racy texts. She said it was a game they had started to play to shock one another and got out of hand.

The guy she texted had worked with her years before and I knew even then, she had a little thing for him. My wife says nothing physical ever happened and she wouldn’t dare go that far. She said she is sorry and she loves me.

This has rocked my world. We have three grown daughters and I thought everything was great. I give her attention, take care of her needs before mine, take care of the house, bills, etc.
I enjoy providing a good life for her.

She says it was a weak moment and something exciting to get away from her boredom at work.

She has deleted his contact in her phone and called him after I found out to tell him they can no longer be in contact with one another.

I nearly left in April because I couldn’t handle not knowing if they had been physical or not. She almost had to go to the hospital she was so upset about me possibly leaving.

I still feel used and cheated on. I guess I will always be insecure now and be suspicious.

I can’t seem to shake this. What should I do?
I don’t want to divorce, we have a good life. But the doubt that creeps in my mind is like a cancer.
The only way she would be able to communicate with him now is via their work email , as they work for the same company. Although I would think if they tried that, the company IT could bust taken and they would be fired.
We are both 59 and have been together 41 years. We were high school sweethearts and got married after graduating college.

I would appreciate your thoughts and input. Good , bad or ugly. Thanks!’