<human>: Can you succinctly summarize the text in 1-3 sentences?

Ive browsed this section a few times, but never felt the need to post until today. My girlfriend's biological father walked out when she was born, and she has esteem issues. There's an older couple at our church that is highly respectable, very spiritual and people I looked up to. Over the last 4-5 months the man and my girlfriend (worship leader) have been texting and calling each other non stop. I finally glimpsed a text or two. 

They were telling each other "I love you", meeting in town to talk, and most recently she admitted today that they had kissed. The texts I've seen also talk about wanting to lay with each other like they did earlier in the day, how passionately he love her and how great of a time they had together. Mind you, this all blew up today. If he knows that others know, it's only because she told him. 

When her mother and I confronted her, she lied saying it was all innocent and that he was helping her with her esteem problems. Then she eventually admitted to kissing him when he visited a house she was watching this weekend. She told me things like that had only been going on for maybe 3 weeks. 

Like I said, he is (supposedly) a very respectable man in the community and our church, and she is the worship leader. I feel that he took advantage of her esteem issues, but they both obviously knew better. 

My question, reddit, is what do you think my next step is? Or, do you any other opinion? If I out him publicly, it ruins her. If I say anything to just him, I'll have no idea if it works or not.
<bot>: 64 year old respectable man in the community and church has been calling/texting my girlfriend for 5 months. Most recently, they kissed. Reddit, what's next?