Why are some aspects of Christian religion so at odds with our biological drive, if it is God that made us?

Is lust itself sinful, or a biological function for procreation as a system?

Is it part of original sin? It wasn't a problem for Adam and Eve if there was noone else.

Pre-religion, lust or sexual desire would be the thing that lead to creating babies before people even thought well enough to make tools or fire right?

But conversely, under religion, for example where pre-marital sex is frown upon, we subvert those basic drives.

Is that healthy or does it make people messed up?

Some people in very strict religions or diets end up cheating it because they just break under it pretty much, defeating the purpose.