IS IT BETRAYAL?

I learnt something from a friends story and she has urged me to share, and here it is 
Chloe and James met at a gas station, Chloe's car had broken down at the gas station on that faithful day and she was already running late since she had to go visit a friend in the hospital, as she got down from her car to go enquire about how she was going to fix her car, another car from nowhere bumped into her car. Chloe was very infuriated because her car was like a baby to her, she angrily went over to question the guy who had bumped into her car, but as she quietly walked up to the guy, he only laugh which only made her more angry but he had gently apologised and gave her a lift to the hospital, she thanked him and walked into the hospital but he had chased after her and smiled at the surprise look on her face "what are you doing here, i thought you had left?" she had asked him
"well, i never got your name" he had answered he watched as she looked into his eyes as if trying to figure out what he really wanted, quietly she said"its chloe, now you can go and thanks for the ride" but he had followed her to the hospital bed where she was seeing her friend, after talking to the doctor in the room, she turned to go and found him there, when she asked him why he was there, he said he was just curious and wanted to know who was in the hospital.
After the hospital incident, they met coincidentally in two other locations and they became fast friends and after two months trhey began dating.
Now after two years of dating and one year of engagement, which is three years of being together, my friend found out that James mistress is pregnant for him, and his mistress is the friend whom Chloe went to visit in the hospital, her closest friend.James apologized and pleaded for forgiveness saying that it was not his fault that he was tempted and once had committed the act, he couldn't stop........................if you were in her shoes what would you do?