Cunning literary detective tracks down the origin of hot cowboy love, to Oedipus the King:

MESSENGER:
I’m sure he recalls old times we had
on the slopes of Mount Cithaeron;
he and I, grazing our flocks, he with two
and I with one – we both struck up together,
three whole seasons, six months at a stretch
from spring to the rising of Arcturus in the fall,
then with winter coming on I’d drive my herds
to my own pens, and back he’d go with his
to Laius’ fold.

In the end, it all goes back to the Greeks.