'Love Island' Star Austin Shepard Reveals He Relapsed During Filming

"Love Island" star Austin Shepard has been open about his addiction struggles in the past ... but not like this. The reality star says he's lost friends to the disease and didn't want to follow in their footsteps.

Austin told TMZ's "Previously On..." podcast, "I know how this road goes. I've got plenty of friends that are not here today that have sadly passed from it. It's either death or a long life of misery."

Thankfully, Austin had a moment of clarity while filming 'Beyond the Villa' in L.A. He says that's when things started to go south with his opioid addiction.

According to Austin, no one in production knew about his relapse, and he tried to avoid filming as much as possible, saying ... "I'm a pretty manipulative, functional addict until it becomes so unmanageable, like how it got."

Austin reveals to us he was in such rough shape when he went to the detox center that he had a seizure on his first night and was sent to the emergency room.

Now, 11 days into sobriety ... Austin is looking healthy again and spending time with his dad ... telling us he now plans to pay it forward and start a scholarship for those in need.