Thomas Brennan joined the Marine Corps in 2003. He was deployed to Iraq and then later Afghanistan.
But the battle he faced when he returned home was the hardest of all.
It came from the traumatic brain injury he suffered after he was wounded by a rocket-propelled grenade while on active duty.
"I really couldn't see a future for myself," Brennan said. "My self worth was gone, it was hard for me to see a future after I took the uniform off."
Watch the video above to learn about how he found new purpose while continuing to serve his community.
More about how Traumatic Brain Injuries affect military members:
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