We do not grow absolutely or chronologically or all of us growing all at once. We grow sometimes in one dimension, and not in another; unevenly. We grow partially. We are relative. We are mature in one realm, childish in another. The past, present, and future mingle and pull us backward, forward, or fix us in the present. We are made up of layers, cells, and constellations. Our writing grows like we do.
I don't know what causes this but I know it is common, and many writers have worked past it. It could be as you say, it could be that you don't want to end the journey with the characters. That's happened to me more than once. I just didn't want to say THE END, and close it up. Be that as it may, here are some ideas I've discovered over the last couple of decades. I hope you find something that helps.
After learning these three techs I haven't had writers block for more than 22 years.
1. Skip it. -- if the scene you are working on isn't flashing up into the visual cortex -- skip it and jump to the next scene, or another chapter altogether. This is one of the reasons I love Scrivener. It allows this kind of jumping with no effort at all, and allows the creation of notes and tags to keep track of your thoughts as you flip back and forth through versions and chapters. So, open up a new document, pick a scene that is in the future that you know needs to happen and begin.
As you are writing, what needs to happen back at the spot you got stuck at will start to be filled in. As you MC does something -- that action will depend on actions happening prior to you jump. Most of the time this is called inference, this deriving what something is because of what something else is.
2. Jump Start -- take out a book from an author you really love. Someone whose prose engulfs you. You can feel the words across your cheeks. Open the book to a random page somewhere in the middle and then type/copy three full pages. Don't stop no matter what ideas come flashing up in your mind. Your Muse had her chance, now she can wait.
Once you are finished, get up, get something to drink, clear your mind and sit back down. Start typing whatever comes to mind, whether it is in-line with the current scene or not. Very soon, within a paragraph, you'll know what needs to be written. Erase what you started with, and continue with the scene.
3. Write what Isn't - I got this idea from the folks at Pixar. An amazingly creative bunch they have over there. One of the head editors Tweeted 22 tips for building creative stories. This comes from #9, of that list, and it is great for breaking up blocks.
Tweet:*** Story basics #9: When you're stuck, make a list of what WOULDN'T happen next. Lots of times the material to get you unstuck will show up.— Emma Coats (@lawnrocket) March 29, 2011
If the scene isn't flashing, then start writing what would definitely not be happening in this scene. For example, your MC is standing on the front lawn of a great estate, trying to come to grips with what "He" said -- suddenly your mind goes blank -- because this is suppose to be a profound emotional moment and you can't seem to find the right direction or words to convey the depth of what the MC is going through. Your muse has left the room... start typing what would definitely not be happening
***
She gazed into the starlight... but a distant thumping sound some where over the trees to the South distracted her. The thumping grew louder, and more distinct. The helicopters -- three of them -- brushed the tree tops as they came in fast and hard, landing on the grass lawns, their side doors sliding open just as the rails touched the ground, and a rush of clowns leaped onto the grass with automatic weapons in hand. The thought to duck exploded into her mind but her body was already hurtling itself into the grass....
***
In no time at all your Muse will come rushing into the room screaming "No, no no no no! Clowns?! You went to Clowns?!"
works every time... good luck and remember, this is the fun part.
