If it was "sex only" that she wanted, she wouldn't be with what you deem to be a "smaller penis sized male"...
What she wanted was to be the one, to be loved and the chemistry in that may have been great, but as others stated, you rated yourself 100% and her 85%... and that's just on sex, you've rated some other girl as " wish I dated you", therefore, you've rated your girlfriend not 100% either, in relationships, with you...
This lady, has never felt she was important enough perhaps only a sex object so I doubt you have any possibility of getting her back until you work out how to "love" a woman for her, not her sexual prowess...
CW
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