It is by no means just the Railway. A bridge over a motorway I cross on my way to work regularly has bunches of flowers on it, despite the extra defences and the Samaritans notices. Beachy Head is one of the worlds 'hot spots' and has a 24 hour anti-suicide patrol plus a weekly runs by the Police Helicopter to locate the bodies. Most of the calls for Tower RNLI on the Thames are to 'Despondent person on Bridge X threatening to enter the water' - sadly they, and the Mets Marine Policing Unit, also recover a fair few bodies.
Up until a couple of recent posts I have been impressed with how the topic has been dealt with - far more understanding for the victims than is common on the Internet. For clarity my post, which has been followed by much more informed coverage of the reasons, ran though what I thought might be 'trigger events'. Not everybody who is Depressed takes their own life but some things make it harder to resist the impulse or push you toward it. This is something I can speak from personal experience on - as can a number of my friends and colleagues.
Its very comforting to take refuge in the thought that those who become so despondent, whether through Depression or not, have brought it upon themselves. Its hard to accept that there is a disease out there that has no visible symptoms, is seductively like your personal experience of being 'a bit sad', leads, on occasion, to major inconvenience and economic disruption and can strike without rhyme nor reason. So its no wonder some people rush to invent a world where its the fault of those of who suffer from it - its much more comfortable that way. None of the people that I know who have attempted suicide or been tempted toward it fit the 'Drink, Drugs, excessive spending' profile. Most are just unfortunate enough to have a chemical imbalance in their brains. The one exception has a major brain injury that was suffered in the service of this country, along with other associated disabilities, each of which that would be 'life changing' on their own - large IEDs tend to do that to the survivors. Sadly, for them, the triggers to their near suicide were indeed the way we, in the form of their neighbours, official bodies and companies working for official bodies, treat our disabled.
Depression is a life-threatening illness that usually strikes without rhyme nor reason and has been suffered throughout history, and not just by the downtrodden or ****less. For example both Horatio Nelson and Winston S Churchill suffered from it. There are also other reasons people take their own lives that have existed throughout history - Romeo and Juliette is a play that has been repeated, with different casts and plot variations, for centuries before and after Wm Shakespeare wrote it.