Jenna wasn't surprised that Ryan was there. Of course, he would attend as well as Jenna was because John was his best friend. It's just that they don't greet each other, as if they don't know each other, or just pretend so that no one will know that they're good friends.
It wasn't easy for either of them to admit, nor was it easy for Blake and Hellen to understand the friendship—which was just an ordinary friendship—between them. Because something had happened before and it wasn't the first time.
Nor can they say that what they have done was an accident. Don't they enjoy it all? Enjoying a relationship like lovers—and maybe they had become lovers who were in love.
That's why Hellen doesn't want to leave Ryan because she doesn't want to be missed again. She wanted to make sure that her husband was served by her in every way. As much as Ryan wants so that the same thing doesn't happen again to their marriage.