I would think being an astronaut has to be only for the most dedicated types. It isn't just the danger: being compressed into such a small module for 10 days with three other people, toilet issues, lots of excitement for the family, but also the fears they have to endure while waiting for your safe return.
Then you land and just want to open the door to feel the freedom of the fresh air, to get a shower, to be back home with a loving family, and so much more. But you have to sit there just floating in the ocean while they set up everything before you can even open the door. It must feel like it will take forever.
You just don't do that kind of stuff without the passion.