Search Results: cheating on facebook

Hey all, so here's the situation. I'm a musician looking to improve my skill and get gigs. One night at a jam session I met this older guy who plays the same instrument as me. He was impressed with my playing and wanted me to come help start up a house band with him at another club. Of course I happily agreed.
Not only did he provide me this environment to play in, but he also took me up as a mentee which I am also grateful for.
A couple of weeks later, I met this man's wife and (the obvservant person I am) I noticed that he seemingly didn't really care for her. This began to bother me as it started to look like the way my dad treated my mom. (Long story short, they're divorced and I choose not to talk to my dad.)
So one night at our performance I put down my horn so he asked me to take pictures on his phone, which I did. He gave me his phone and told mw the PIN and I couldn't help but notice that he has Tinder on his phone, which obviously reinforces my suspicions that he doesn't love her and adds that he may be micro-cheating at least.
I've been working with him to improve our exposure and our audience has been gradually increasing each week. I record videos on my camera and post to Facebook. He loves the work I do and so do I.
Fast-forward to tonight. This was our best night so far, both performance-wise and attendance-wise. My mentor's wife was there too, and she helped take pictures. After the show ended, while he was packing his equipment, I sat down and talked to his wife. Our topic of conversation became about him and his drinking problem, and then I reluctantly discussed my suspicions to her, including Tinder on his phone. She had his phone so I showed her it was there. I saw in her face she was devastated. I feel bad that I did it, but it would kill me to not get it out.
He doesn't know yet, but I fear I may lose this awesome oppotunity and mentor because I did what I thought (and still think) was the right thing to do.

What are your thoughts?