BROWNSBURG, Ind. (WISH) — A Brownsburg teen living with a debilitating disease is optimistic about a future he was never promised.

In the past, people diagnosed with mitochondrial myopathy — a condition that causes muscular problems — rarely lived beyond the age of 16.

But 18-year-old Andrew Rusk is on track for a high school diploma next year, despite the limitations he faces.

Rusk’s life with mitochondrial myopathy means he has weak muscles and limited energy.

“My doctor said it looks like I have the lungs of a … what was it? An 80-year-old smoker,” Rusk said.

Rusk’s condition makes it hard for him to go to a brick-and-mortar school. Doctors have told him he would face limits throughout his life.

“I’ve been told about two times that — was it two? That I’ve had six weeks left to live,” Rusk said. “I’m here! Still kicking! So that’s good.”

He is set to graduate from high school in early 2020 thanks to an online public school called Insight School of Indiana.

Through the program, many students with conditions like his get to have a social, educational experience that works around their needs, unlike the other methods he’s tried.

“It’s so different,” said Andrew’s mother, Karen Rusk. “When he was Skyping in, everyone else was in a classroom. Everyone else was having that direct learning experience and he was the only one not having that direct learning experience and so everything was still very much having to be individualized.”

“It didn’t go well,” Andrew said. “Let’s just say that. It didn’t go well.”

Rusk prides himself on getting good grades.

“Whenever it gets below an A-minus or an A-minus, I’m like mmmmmm,” Rusk said.

Rusk said he sees a real future for himself because of the program.

“I can get a job in the future,” Rusk said. “Which I hopefully want to do. I always dreamed of working at Disney. I think right now I’m going to be a youth pastor, but if I had a dream job it would definitely be working at Disney.”

Rusk said just because someone tells you life will turn out one way doesn’t mean you shouldn’t try.

“Live your life,” Rusk said. “Live like it’s every other day. Enjoy what you have left. And if you live past the six weeks, hey! You live past the six weeks! You walk into that next doctor’s appointment and say ‘What’s up?’”

Rusk said he is looking at online college options to further his education after he gets his high school diploma.