Premature Romance-ulation?

I have a theory that romance novels where the starstruck couple reach an intimate relationship by the halfway point are boring to finish for the reader.

It's the same with TV series.  Once the sexual tension is resolved, viewers tend to drop off.

Is it better to keep the reader on edge waiting, waiting, waiting?  Yes!

Let me know your favorite books with a romance that made your heart soar or ache for the (hopefully) happy couple.