Long story short. I have this group of friends that I usually hang around. A girl in this group, let's call her S, and I started to have a FWB relationship (had sex 3-4 times) . Last Wed, she called me out for a walk and told me that she no longer wanted to be FWB and just be friend. I just stupidly said 'okay' and left it as is. What can I learn from this? Should I have done anything better to retain her? She is definitely a ONEtitis for me since she is the only person that I currently have sex with.