I [26M] found nudes and videos of my [24F] online. How should I approach this?

Background: me and my gf have a great relationship of about one year besides one thing. Our sex life is terrible. She has a very low sex drive. I’m defiantly on the average of sex drive. I don’t expect everyday but typically 3-4 times per week in my last relationships. And that’s been great!

Well it’s been really bothering me… she’s constantly denying my advances to the point we have sex weeks in between. When we do she’s really never into it. She says it’s not me it’s everyone she doesn’t mind sex but she doesn’t need it. It’s been driving me nuts. I’ve mentioned it in the past but her excuse is she’s tired or her stomach hurts. She does have stomach problems and she does work a lot. So as previously mentioned about a week ago I decided to just have an actual conversation about it. I’ve been waiting for the right time and BAM… I see it on a site. Her nude pictures, dancing naked flaunting her parts and videos of her pleasing herself very aggressively. They’re old prior to us dating. I’m assuming one of her previous boyfriends leaked them. I’m crushed… this sounds so selfish and I look like a terrible human being. I’m obviously very upset someone would betray her trust and post them and I feel terrible they’re forever out there on the internet for the world to see. But she’s never once sent me something remotely close to this. I’ve even asked. I DONT KNOW WHAT TO DO. I want to talk about or sex life and how I feel about it but I feel like I need to tell her what I found. I just don’t see how to do it. I would come across as a piece of garbage tearing her down telling her st the same time. I want to talk about how bad our sex life is. I want to say you send and do this but never once have I gotten something like this, on top of our terrible sex life. I NEED HELP.