It's worth pointing out that mental health issues can be circumstantial, or clinical.
If there is a trigger, health, or environmental cause, then you can overcome it on a permanent basis - this could be a bad relationship, your living circumstances, or just the "way things are going".
Clinical depression is a bit different - it's something either you're born with, or develop over time. There may not be a logical reason for what you're feeling, and you could be a billionaire with the life of larry, yet you feel like you can't cope. You don't ever 'cure' things like that imo, you just 'treat' it - whether it is with methods of learning how to cope with it, ignore it, or otherwise use medicinal treatments.
So some people do recover, whereas many don't.
Depression is made a mockery of in the same way that Influenza is (i.e. 'the flu') - too many people use it as a term to describe their own attention seeking or general low mood, which desensitises the public perception of what depression is, and what recovery is.
It's well known that mental health in football is completely neglected, so I hope both Aaron begins to recover and that it raises awareness towards depression, and starts to dispel the notion of "how can a rich footballer be depressed?".