Was seeing this girl for a couple months. It was just casual weekly sex, no exclusivity discussed. But last time we got together, she had just gotten back from a girls' trip and had a faint hickey on her neck. I brought it up and she said she had a ONS on her trip. She wanted to have sex with me, but I kind of got disgusted. Not because I felt cheated, but because I could have had sex with her and been exposed me to STDs if I hadn't noticed the hickey. I told her we better wait until she gets a clean STD test and she just stood there in disbelief. She walked me out and slammed the door. Was I out of line? I'm having conflicting thoughts about this.