I think we are so conditioned to think that break ups or endings must be high conflict in relationships with a bad guy and a good guy. This is an example of two people both doing the right thing and not working.
You both went on a real life date instead of texting forever and wasting emotional energy before a face to face meeting. You both tested your physical chemistry early. You wanted to keep going out so you planned more dates. She did not and told you so. You handled it with grace and respect. All around best case scenario for two people to not continue dating.
Who knows maybe you will run into her at a bar and her friend will be interested in you. You have shown yourself to be a good person. She might vouch for you but even if not good vibes are out there. This was a success not a total success but a success
Really the only ones