Please don't leave her to cry it out. Have you read the BW books? If so, I'm sure you read that Tracy was a strong advocate against CIO and CC as she felt they only broke the bonds of trust and might make things worse.
That said, big hugs to you! You are a great mom for trying to figure this out and we can definitely help.
First off, I think her A times need some adjustment. It's great that you try to hard to follow her cues, but at 8 months, sleep signs can be confusing - yawning or crankiness can also mean boredom or something else. First off I"d establish a consistent wake time - if that time is say 6:30 am, I'd hold off the first nap until 9:15 - and I would not let her sleep more than 1.5 hours most. Second nap should then start approx 3 hours after end of first nap and can go up to 2 hours tops and then you'd want bedtime about 3 hours after end of second nap.
If she seems cranky/tired sooner, try to extend her A times gradually - change activities, go for a walk, read books or cuddle, etc. Maybe extend 15 minutes every 3 days so she doesn't get too overtired.
Teething can be a factor too - you can try giving her some Hylands Teething Tablets or Motrin before a nap.
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