Kaboom

Just when you think you have it all, it all goes Kaboom...

Clay Maslowski had a happy, satisfying future ahead of him.
A promising career in the United States Army, with his enlistment
about to reach its expiration. He plans to sign reenlistment
papers for another four year commitment, as soon as he returns
from his deployment to Afghanistan.

His dream of becoming an Army Ranger is about to come to fruition.
A spot in RASP, the elite Ranger training school, waits for him, as soon
as he returns from his deployment to Afghanistan.

His high school sweetheart also waits for him back home.
Their love has endured despite being apart for most of his time
in the Army. Clay plans to use his combat pay and re-enlistment
bonus to purchase a ring and propose, as soon as he returns
from his deployment to Afghanistan.

Then his world went Kaboom.

Instead of returning home as a Ranger, a soldier, a complete happy
man, Clay limps into his parents' house with crutches and
a cane and a hideous mechanism of titanium where his left
leg used to be, retreating into a world of despair and pain medication.

How can he survive Kaboom?