Well suicide can either be a cry for help or a decision that life isn't worth living. Maybe more men decide the latter.
I also think the financial/work aspect is being overlooked. At around 40 a man will be most likely to have kids/mortgage/wife to support.
For him, it looks like another 25 years of the same 9 to 5 drudgery. This is probably made worse by the face that his spouse is at home or working part time looking after the kids and is pretty much put to pasture, the hard part of her life is over, alot of women don't pick up their career after having kids and will rely on their spouse for support.