Make Something Happen by Ann Haywood Leal
You've picked your character and you've dropped them into a place, and you've given them a problem. Everything is going smoothly -- with your writing, but not with your character, hopefully! Then without warning . . . you are stuck. Your story is going absolutely nowhere.
Finally you realize what's wrong. Well, you secretly know it in the way back part of your brain, but you can't bear to even think it out loud. There's a problem, sure. But the story may not be moving forward because your problem isn't strong enough. It may not be devastating enough. Your character's situation may have been good enough for a subplot, but you realize it will never be strong enough to carry you to the end of your book.
Here's the thing. You have gotten to know your character. You love your main character. You know what your character would say or think in any situation. That's good . . . right? Of course it is. But you might have fallen into a very common trap. Since you love your character so much, you may have been being too nice to her. It's possible you have not made the situation hard enough.
Be brutal. Put her in a tough situation, and then take it up a couple more notches. See where it takes your story. You may find your character going on a bumpy ride that won't allow your reader to leave the couch until the very last page.