I live with my brother and he's been with his girlfriend for 3 years now. Me and her get along great, I think she's really good for him and is a really awesome girl.

My brother had an online meeting not too long ago and just before it I asked if he had some picture in his phone and he said that he thinks he does and gave me his phone to search for it while he was in the meeting.

While I was in his gallery I saw a folder that was not locked, just stood there at the end with all of the rest and in there were a bunch of nude photos and videos of his girlfriend. I knew it was extremely wrong, but I just couldn't help myself and started going through it all and couldn't stop.

This has changed how I see her a bit and ngl, I liked what I saw so my head's filled with sexual thoughts about her, especially when I see her. It's hard to forget what I saw.

I feel like a total piece of shit because I feel like I disrespected her and my brother, but what makes it even worse is I also have a girlfriend so I feel like I'm disrespecting her too. And the worst part is all 4 of us get along so well and hang out and go out and we really have fun as a group.

Just to be clear, I am NOT in love with my brother's girlfriend, this is a merely sexual attraction, but I still feel shitty. I could always tell she's an attractive girl, but seeing everything I saw really made me see her in a light that's a lot more sexual. I'm hoping it'll pass soon because I don't know what to do, I can't say anything to any of the people involved.