What makes a person find everyday living really hard to cope with? I reckon depression could be the culprit?

but any other ideas out there?

Depression -as you put it- is like a disease -something external that invades the mind and makes an individual unable to cope!! As I see it the medical profession sees it in the same way and tries to give their patients a quick fix in prescribing anti-depressants-Drugs that alter the mind and give horrendous side effects that have the potential to kill or put a person in a frame of min to want to commit suicide!!
Depression ,to me ,is a symptom only of a person's difficulty in determining a course or direction in one's life!! It is an inability to decide and to solve problems leading to frustration and depression!!!
It is not unlike a mouse caught in a live trap and cannot find a way out !! It will die -not from the trap but from frustration and hopelessness!!!
With drugs the problems remain -we only trick the mind into believing otherwise and redirecting its' attention!!
Education is one of the solutions!! Giving a person a wider ability to solve problems by giving more choices and knowledge to use those choices!! This gives an individual vision to see beyond the moment and to perceive a future!!
With a sense of future comes a sense of hope by way of reason !! With hope there is less frustration and less depression!! It will not disappear all together in our lives -since we are human -but diminished enough whereby we can cope!!!!!!
Just a few notions from this humble attempt to answer !!

Also anxiety
Even when a person is back in a happy frame of mind, they might have missed all the steps to living a normal life. They might have missed learning how to drive, how to pay bills, how to interact with other people, how to get a job ...missed all the steps between having the idea and being able to achieve it. This would make it even more difficult to escape becoming depressed again

Sometimes I think people are trying to live a life that just doesn't suit them. They might think they should be a doctor, their family might think they should be a doctor ...but their soul wants them to keep bees and a dairy cow (c;ll

Your question is not specific enough to respond reasonably. But, depression, bi-polar disorder, ADD, are the diagnoses of the day. Don't fall for it.
Try again with some detail about your difficulties and you may come up with an answer you can use. There are therapists and psychologists on this site who may be able to offer some real advice.

yesterday, i watched this film [radiant city] about surburbia and suburban sprawl, and it says that alot of kids in the suburbs are more likiley to be depressed because they dont have people around them to talk to, especially if their parents are at work and everywhere is a driving distance away. i dont really know if that has anything to do with it, but it was really interesting.

Everday living could be difficult if you have no family,few good friends and no support system. It can also be hard if you don't like your job or don't have enough money for the things you want or need. Depression can certainly make things hard.

You are right. Why? do you find yourself having a hard time coping? If you do dont give up, all things shall pass. Its only temporary.