S.M.
Have a pediatrician check her tonsils just to be sure. My daughters were so large that she would just start to fall asleep, the muscles would relax and then she would wake up because she couldn't breath. She'd be so tired she wasn't always awake, but was always whining and moving around in her sleep. I believe learge adnoids can do the same.
Also, it may be good for you both if she is in another room, with soft music. Is her skin dry? If so, she could be very itchy. Does she have a diaper rash? Does she eat well in the evenings? She could be hungry? Is she dressed too warm or is your house/apartment too cold?
Is her bed comfortable enough? I know they say hard and tight sheets etc. But I think kids are a little more comfortable on soft blankets. She's really past the sids worry. You can experiment with that.
Does she like very soft things? Maybe you could get her a soft and silky blanket she can hold to her face?
Keep trying. Something is making her uncomfortable.