Hey smith2060 - sorry to see down like this - depression is a real horrible thing when it kicks in and leads us to presume dying would be better than life.
As for your friends, perhaps they are young and can at least plead ignorance. It is perhaps a lot to expect for even a friend to understand the condition. By not taking you seriously - they are not doing any favours. You should never tell anyone who is suicidal to 'don't be silly' or 'it will be fine' - but not everyone is aware of the facts of depression - I guess like a lot of illnesses, people do not truly appreciate the suffering unless they experience it first hand. This is not to say they are not friends. It's just difficult for people talk about - this I know from experience. Best to limit who you tell to a trusted few - and when you feel a bit better and can cope - its up to you who you might tell.
When young its more difficult to talk about depression - but you really should talk to someone. At the very least you ought to go to your docs - get some medication maybe or counselling if you think the depression is rooted in some past event or events.
Therapy can help in ways of coping - techniques and so on to 'train' yourself to cope better.
Depression is a thin line - you cross it before you know - few seem to realise prior to depression that they need help. Even so - now you are here you ought to get some help and meds would likely be the first course of action.
When anyone feels like they want to die - for extended periods of time - medication can be a life-saver as it can help with the biological, chemical. electrical processes which take place in our brain. Medication can help - it is a fact that many drugs effect the mind - but anti depressants lift the mood without it being a drug experience. Even a subtle shift can help immensely as testified to by many people here.
Hope you get better as the summer reaches us - try to have a little more faith in yourself and try not to let the negative voice of depression call the tune. Find things to busy yourself with in the meantime - try not fall into the trap of just staying indoors.
Get that help also! Its not right for you to suffer in this way and my guess is that when in a storm any port will do! Nearest port for you is the doctors - dock in there - explain how you feel and be honest.
Getting help now is far better than leaving depression to put on muscle.
Good luck and God bless
Hope happiness comes your way soon - at the very least you need to be able to think that it CAN happen to you.
What of your studies? Anything going on there or with work? (edit - I see you've taken a month off work)