Reid claims that the diagnosis has made him reconsider much of his life after spending years being bullied.
He told the Mirror that he has faced persecution and always felt different to others and been treated poorly his whole life as a result.
However, things are starting to make a bit more sense to him after he was diagnosed with Asperger's Syndrome.
He explained: "It's a relief in many ways but it's a bit unnerving because it's coming to terms with new things, but it also explains so much."
Reid found out about his diagnosis after he met a family who had an autistic child. After running into the child in a park, he started talking to his family, who have several autistic relatives, and claims they later suggested that he take a test.
He continued: "I was so friendly with the children and the parents started to notice so many traits in me. They saw that in interviews I can sometimes be so together and then I can completely fall apart.
"They said they thought I was autistic.
"I've always thought of autism being like Rain Man and thought that wasn't me, but understanding it more now it makes so much sense."
Alex says that the diagnosis has helped him to explain certain behaviours, including how he has learned to cope with his years of bullying by hiding behind a 'mask'
He went on: "I've achieved so much and I felt like I could cope with anything.
"I've been so horrifically bullied throughout my whole life. I was the kid in school who asked the questions no one else would and I'd be laughed at, I was the kid that the teachers would say had to try harder and they didn't understand it.
"Even in the army I've been bullied and I've been bullied for being different. This has kind of made sense of why.
"Although I felt like I could cope with anything and I'm big and tough and strong, actually deep down there's a little boy crying."
Reid added: "I've put on all of these masks to cope and protect myself and created all these different personalities - I'm an actor and I'm great at acting because I can pretend to be these different people.
"But ultimately deep down there's a little boy crying and not liking it.
"I'm soft but I can be really tough when I have to be."
Reid now hopes that his experiences can help others achieve the courage to get tested, or to learn more about their own autism.