Ends are the dessert. The stuff that fills you up but leaves you hungry for more.
Ending are hard to write. Really hard. I've rewritten the last quarter of this draft three, maybe four times, trying to get everything right. Because it's the black moment, the finally battle, the resolution and that tasty bit that makes a reader want the next book.
They suck the life out of you! Mentally, emotionally, and creatively. They're like the writing version of vampires. Only less sparkly. Though granted, there are a lot of sparkly endings out there, and if that works for your book, then go for it. I mean the actual writing.
When your ending sucks everything you have in you and demands more, and you feel like ripping your hair out, banging your head against the wall, or taking up hard liquor, take a deep breath and give it more. I love telling people that nothing in life worth having is ever easy. A great ending is defiantly worth having, and it's not easy.
Don't give up, though. Dessert is the best part. For you and the reader.
Disclaimer: This post was written after a long day of working on the ending of a novel. The writer cannot be blamed for any or all confusion this post might cause.