You've tried it with sex now try it without. At the very least, you'll be able to compare the outcomes and withhold other parts of yourself, too. Become a mystery that he can explore. But continuing with the same approach and expecting different results is not rational. You're losing too many games by revealing all your cards.
Courtship is a process.
You don't start at the end point you work towards it. And, in the meantime, expand your resum personally and professionally. Take courses of all kinds, bone up on computers or languages, cooking or tennis, skiing or accounting. Get degrees, travel, volunteer. Make lots of contacts.