Adjusting Trauma Levels

There's this problem I've had for a long time.  I might even have blogged about it before; I've been doing this thing for about four years now and I can't remember every single entry I've made.  :P  It's a simple thing, but it still stymies me:

I have serious trouble putting my characters through serious trouble.

Some writers have a real gift for putting their characters through hell.  The trope "Trauma Conga Line" exists for a reason, and there's a reason that page has so many examples it needs separate pages to hold all of them.  The best example I can think of for this is Harry Dresden of Jim Butcher's "The Dresden Files" series - over the course of fifteen books, Harry has had maybe fifteen things go right for him.  I'm exaggerating a bit (it's at least twenty), but if something bad can happen to him, it either has or is probably going to.  Especially in book twelve.  Ye gods, book twelve.

This is something I love as a reader, but I've never really been able to do the same as a writer.  And as I plot and prepare to write yet another book, it's starting to bother me.

As far back as I can remember, this is an issue I've had to deal with.  In my early stories, characters figured things out with ease, fell into the information or plot device they needed with little effort, and were always able to figure out how to triumph in the end.  I've gotten better about it over the past few years, even been able to have people lose limbs and eyes and occasionally get killed.  And then there's the emotional trauma.

But I can never shake the feeling that my characters get what they want and get their happy endings too easily.

I think part of it is that I want to see these people succeed.  As I talked about a few entries ago, I don't want to write stories that are nothing but doom and gloom.  I have no trouble coming up with challenges for my characters, as that usually makes up the heart of the story.  In the book I'll be starting soon, the entire middle is the crew gathering items they need for the race/scavenger hunt from across half a dozen different worlds, and that's a daunting set of tasks that changes them in unexpected ways.

None of them come out of it the same in the end, and not everyone comes out alive.  But I still feel like it's all too easy for them, despite everything that happens along the way.

I know that if I wanted to, I could drop mountain after mountain on my characters.  But I think there's a limit to that.  Eventually, stuff like that stops being a story and starts being just a laundry list of things going horribly wrong.  Everyone has a breaking point, but I don't think that every story needs to be dedicated to finding that point.

This leaves me not entirely sure how to find the middle ground.  Obviously, I can't go too easy on these people, as that would be boring.  Going too hard on them would likely result in character rebellion by way of them refusing to continue on their stories because I'd done too much to them and they were ready to lay down and die.  And trying to find a middle ground leads to . . . this blog entry.

So now, I ask for advice.  How do y'all deal with this?  How mean do you think you can be to your characters and still get a story that works?  And how do you know when you've hit that point?