The organisation, called Soldier On, said the war would not be over for some veterans who have been physically or psychologically injured.
Latest figures from the United States show more American soldiers died from suicide last year compared to those in combat.
Soldier On co-founder John Bale said sometimes it could be as difficult to come home as it was to go to war.
"I guess the biggest struggle is just re-integrating back into society," Mr Bale said.
"Simply shopping [and] being around their families is quite difficult because what they've seen and what they've been through, it's difficult to fall back into that day-to-day humdrum of things. And that hyper-vigilance... can stay for a long period of time."
Mr Bale said the difficulty to re-integrate could be attributed to psychological injuries which could remain for long periods of time.
"One [man who] came back, who is one of our wounded ambassadors, was in an improvised explosive device (IED) attack, and if you look at him there's absolutely nothing that would distinguish that he has been wounded, but the effect on him was so much that when he came home he couldn't remember his children's names," he said.
"He still struggles on a day-to-day basis being able to complete simple checklists and simple things and forgets a range of activities.
"The explosion may not actually take off an arm or anything like that, but there's a lot that have that traumatic brain injury."
Luckily, Mr Bale said the stigma for soldiers not wanting to be seen as weak was changing.
"I think that was one of the biggest things that has been a part of defence culture, but I think with recent events such as General Cantwell's book, Exit Wounds, that is slowly changing, especially with the Special Forces guys identifying that this is a real thing," he said.
"Post-traumatic stress disorder and all the other psychological effects are real things and identifying them, working through them and being able to control them, can actually allow you to get back into your job fully, and therefore it's not a sign of weakness to identify to your mates and also to your family that you have this problem and you need support.
"So I think that has changed, and I think that's a really wonderful thing."
Mr Bale said having learned from the mistakes of the Vietnam War, Australia needed to build a community to support veterans from Afghanistan.
"For them, it's a consistent lifelong effect not just for them but also to their families, and I think we as a nation need to recognise this is going to be a lifelong support from the whole Australian community."