15 month old just having horrible sleep issues

I am having a hard time getting my little girl to go to sleep. She is 15 months old and lately she has been fighting sleep and why I do not know. It's really taking a toll on the family right now and we are extremely stress out by it. It feels like medically there is something wrong, but everyone we talk to doesn't' seem to think so. They just say she is spoiled or we need to be more strict. I don't think that's the case though.

We have always kept a routine with her. Everything is on schedule and has always worked out. When she was a baby we went through colic and crying/screaming spells a lot, but she eventually outgrew the colic. It would hit her the same time every night and last for hours. There were a couple times we even took her to the hospital. Nothing of course was wrong. So we would rock her to sleep til she stopped screaming. She had always took 2 naps and then slept all night with no problems. Rarely would she wake up for a bottle at night.

Then a few months before she turned 1, the problems started. She stopped taking her naps. Then she stopped eating and started getting really picky with food. Still, she only eats here and there and sometimes goes a couple days without eating but a little nibble here or there. Then she will eat a whole meal the next. We try to give her all the stuff we know she likes, but she just wants to throw it on the ground. She wastes so much food it drives me crazy. But her not wanting to eat is even worse, because I know with a full tummy she will sleep better.

Anyway, she stopped taking naps and now when bedtime comes (which is 6:30) she starts screaming at the top of her lungs blood curling screams non stop for hours on end. It's not the oh I'm so tired, but too stubborn to fall asleep cranky scream...its the I'm a complete brat so I'm going to scream at the top of my lungs and shatter glass type scream.

We try to not give in and bring her back out of the bedroom and just let her cry it out, but it doesn't work. We eventually have to go in there and get her, because she has screamed for so long and so loud and hard that she now is soaking wet, she's spit/drooled/spit up milk all over her face and she is sweating and beat red in the face. One night she even choked herself on her spit because she was splitting up all over the place from screaming so hard.

So even though she gets up before the sun even comes out some mornings, never takes a nap, we extended her bedtime to later. We try to feed her later (sometimes she eats most times she doesn't) and then put her to bed much much much later. For example, one night she went to bed at 8pm, screamed for almost 2 hours straight, we brought her back into the living room after my guy stayed by her crib trying to sooth her to sleep which didn't work...she stayed up til 10pm, we tried yet again to put her to sleep and she did the same thing....then finally at almost midnight we put her to bed and she screamed a little and went to sleep. She still managed to wake up through out the night crying and got up at the crack of dawn wide awake and gave us a repeat til midnight again.

Now, this isn't healthy for her or for us. We need our alone time and she needs her sleep. I am a stay at home mom, but by the time my guy gets home for work and is wanting to spend time with me its impossible, because we are constantly struggling to get her to sleep. By the time she does fall asleep we are so stressed and its our bedtime too.

And I know she is tired, because she is staggering throughout the day and is cranky and crying all day long. One little word to her makes her cry, she is constantly rubbing her eyes, she pulls at her hair, and just is real fussy. The days that a miracle happens and she goes to bed on time and sleeps all night she wakes up and is a real charm to be around. Those day have gone away though and we are stuck with a very cranky toddler that wont sleep and we don't know what to do. We have taken her to the hospital and had tests done. Everything came back ok. I would love to have a baby sitter come bedtime so I could not deal with it for just one night, but I can't afford that unfortunately. I'm tired of ppl saying she probably just spoiled. Even spoiled kids need a good sleep eventually!! Her on the other hand.... any suggestions?

btw - I've tried cat nip tea, lavender bath before bed. lavender lotions, quiet times, reading a book before bed, turning down all lights before bed..anything you can think of , I've tried it. And even when she does fall asleep, she still wakes up all night screaming and then falling asleep and screaming and so on...