How I got into SPH. So when I was 23 I was dating a girl wh..

How I got into SPH.
So when I was 23 I was dating a girl who was 19. It was going really well, or so I thought. She was very pretty and loved posting on instagram showing how good her life was and all that. She would always love to show me off on there. If I take you behind the scenes however, things aren't exactly the picture she was painting for us.
The first clue I got of something was when I stupidly asked her about penis size. To which she told me I was probably average and that she doesn't really pay attention to it. However, only a week later she tells me about a dream she had where she was masturbating a cock from behind. I asked if it was me in the dream and she got very shy and said it wasn't a person, just a cock. I asked if the cock was bigger than mine and she said yes. I tried to unravel this thread more and she told me it was probably her first boyfriends and that it didn't matter. This got me questioning if she actually likes my cock, so I asked her to just be honest with me and tell me if my cock is too small. She paused for a minute and said, "your cock isn't very big and I've only really experienced bigger cocks so I'm still adjusting to yours". I left the conversation there but obviously this was constantly in the back of my mind.
A few months later I decide to clean her room for her when she's not home, her flatmate let me in without thinking much about it. While I was cleaning her room I found an open box of XL condoms in a box under her bed. I figured they were from before we were together but I took one and compared it to the condoms I use (picture of the difference). I found this so hot that my girlfriend has taken much bigger cocks than mine and I literally lay on her bed and jacked off. I even put one on and it was so loose around my small penis.
Another few weeks go by and I find myself alone in her room again, so I open the box I found the XL condoms in and I immediately notice there's only 2 left when there had been at least 7 in there when I first looked. I knew right away what was going on, I started to put it all together in my head. I knew it had to be the guy she studies with, I had even dropped them off at the library in the past.
I asked her if she was cheating on me and she denied it but I said I had proof that she was and she just started crying. I asked if there was a reason and she just said they got caught up in the moment once but I said I know you have had sex with him at least 5 times in the last two weeks. She asked me how I knew and I told her. I leave it for a day and we get together to talk about it, I asked if my penis was an issue and she told me my penis was too small for her and she didn't know how to tell me without hurting me.
We eventually broke up and she ended up getting together with him. So that's how I got into SPH because I think back on that time and it just turns me on knowing my penis was too small for her.