Not Sure What To Do

Since Halloween night Chloe has not been able to fall asleep in her bed. I'm not even kidding you when I say this, she was seriously the best toddler ever when it came to naps and bedtime! I could not complain! I could put her down in her bed, give her kisses, rub her back for a few minutes and boom! Done! I'd leave the room, close the door and not hear a peep out of her all night long. But, NOW?! Nope....she refuses to lay down and relax in her bed. The costumes and masks she saw on Halloween legitimately scared her. Ruined her is probably a good word to use. This has been torturous for me! Now, don't get me wrong, I love the night time snuggles that I've been getting, but when it comes down to having time to ourselves at night. We went from over 2 hours to close to UNDER an hour. Chick isn't falling asleep until close to 9pm now.....and that's only because we're on the couch watching Barney or MMCH.
I seriously don't know what to do about this?! Will she break from this? Is this just a phase that will pass? Do I need to push her to break this? Do I just let this phase pass? I'm desperate to have my good bedtime toddler back! We have tried everything. We've moved bath time back a half hour to see if she gets tired earlier, we've tried reading to her IN her bed, but she just won't lay down.....she just wants to go back downstairs. And once she starts crying, it's all over. She just won't stop. I know that if we just let her CIO, she would eventually fall asleep....(maybe) but seriously, I just can't do that to her. I feel like she's really scared in her room in the dark and I would feel way to bad about that. But, let me say something else....she isn't in complete darkness. We have a battery operated candle in there and she's got a light show thingy on her crib that shows on the ceiling. So, she's not in the dark. But, if we leave her she just screams......HELP ME!

Has this happened to you? What did you do? Did it pass? I need some advise and help please! Ok...GO!