The former Arrow star went public with his sexuality earlier this year (16), but critics were quick to judge him for not being more candid with his personal life, prompting Colton to enter rehab to deal with anxiety issues from all of the media attention.

He is now sharing what led to his personal struggles by opening up his diary to Paper magazine.

"Something's been off recently," he wrote in the first journal entry in 2014. "I honestly wake up after five hours of sleep wide-awake. It's probably from the bottle of wine I drank before I finally fell asleep/passed out or the amount of pills I'd had. I read up on why I'm experiencing numbness and lack of circulation in my hands and feet and it's due to the stimulants I've been taking for quite some time now. It causes the blood flow to move toward the heart therefore removing it from the lesser needed places like my hands and feet."

The 28-year-old went on to reveal he felt like a "shell" of himself as he started suffering from agoraphobia.

"Now I'm so closed off to the world that I can't even get up enough courage to go in public," he explained. "I'm afraid of people and have become agoraphobic."

Colton went on to write about wanting to seek help, but admitted he didn't know how to ask for treatment. He also questioned why he struggled to find happiness in his life and claimed he was unable to recognise the person he had became.

"There are so many things I want to do in this life but I don't know how to start," he added. "I don't know who I am anymore...Why can't I just be happy in the now?"

"I'm always searching for the next thrill, the next break, the next job," he continued. "My life is a drug. I'm always chasing the next high. To the public eye, my possibilities are endless, but in my mind, I'm fading away and battling to hide the pain and emotion that has plagued me my entire life. I've cheated, lied and finally owned up to it... I am lonely. This is my fault, though. I don't want to let anyone in. People don't understand the things you give up when you step into the limelight. No one really wants to get to know you."

However, the actor also shares an entry from last month (Nov16) to show how much his life has changed for the better since seeking help.

"I always look at old photos hoping to relive the memory," he wrote. "But what I'm finally realizing is that I can't and wouldn't want to go back to that headspace ever again. So clouded and unsure about myself, my life, my privacy, my mental health.

"I'm finally in a position where I can say I'm the happiest I've ever been. I've accomplished so much with so little and my smile is finally not forced. I've taken control of my own life for the first time and won't let anyone silence me or my passions ever again. I'm finally free. I'm successful. I'm independent... But most of all, I'm outspoken."