you haven't met the drivers out here. They're bad, there mostly aren't physically separate bike lanes, and you often don't even get a ticket for killing a bicyclist. It's not worth it.
edit:
Also -- sample size of 13 -- 70+% of the people I know who bike commute daily have been hospitalized. I also know someone who did 6 months in a nursing home after some bitch ran a red light, hit him, and cracked his pelvis; he won multiple surgeries and the inability to stand up for months.
That's a good point. I'm too NL centric here, old ladies here would have no problem with a bike trip on that distance but not having bike lanes changes the picture quite a bit, especially if the drivers do not exercise care.
My mom routinely does 100 km trips and she's in her seventies.