What should my wife do if she attends a class reunion and rekindles her first love?

My wife and I have been married for 5 years and we have a lovely baby. Their jobs and incomes are stable, and their lives are generally dull.

My wife attended a classmate party this year, which completely broke the peace of our family. Since coming back from the party, she has spent more and more time playing with her mobile phone. After returning home, she just chatted with her mobile phone and gave a hearty laugh from time to time. I asked her what she was playing, and she said she was chatting with her colleagues. I trust her and never look through her cell phone.

One day I went to the toilet in the middle of the night and saw her mobile phone screen flashing, so I looked at her mobile phone. A man named "He used to be" sent a message at 12: 30 in the morning: Honey, are you asleep? The feeling of our reunion is arranged by heaven. Now I want to chat with you and be with you every day! There was no information before this message, which means that my wife deleted all the chat records! I realized at that time that there must be something fishy in it! This news is too ambiguous!

I put up with it this time, and then I paid more attention to my wife's mobile phone. Three days later, she went downstairs to get the courier and forgot to bring her mobile phone. I took a quick look and saw the chat record, and I was furious!

It turns out that she met her first love! The two have rekindled their old love! I still want a divorce, but fortunately I found out, otherwise I would be miserable!

Should I tell her the truth now?

After all, my son is only 3 years old. I don't want him to grow up in a single-parent family. What should I do?