The first thing that sticks out at me is the last sentence- about seeing the stars. If she is awake late enough to see the stars at 2.5, that is TOOOO late, in my opinion. My daughter is the same age and goes to bed at 7pm and sometimes even 6:30 if she is really tired. She still does a nap from time to time as well.
They are burning LOTS of energy at this age and need the exercise, but also need a consistent and early bedtime. Generally, I find that the later she stays up past that threshold of 7pm, the harder she is to go down and then will be "wired" until 11pm if we let it. So that is my first thought- a much earlier bedtime.
The other things are definitely about control- she wants to have it and she wants you to reassure her that you will be there for her. I don't know how leaving her affected her, but it sounds like she is a pretty sensitive child and picks up on things around her (surroundings, emotions) pretty easily and then tries to process that through control because things (that to adults are no big deal) feel out of control and scary to her. Maybe she's a bit more sensitive than other kids this age and that takes a little different parenting tactics (hey, it took me 10 years to learn how to parent my 10 year old and I am still no expert!! she's sensitive too!)
I would explain things to her in detail about what is going to happen and then stand firm, but positive. Reassure her that you are there for her. I hate to use the old "she's not getting enough attention because you have a baby too" line because I think that can be nonsense and it DOES sound like you are trying, but let's face it, I'm sure you are stretched thin, and if she's sensitive, then those emotions just sort of feed on one another round and round- she gets sensitive and rebellious, you get frustrated, she senses it and digs in more.... ugh. Been there done that!!!
One thing that has helped me is to not listen to what my daughter SAYS but to watch her body language (this is going off my sensitive 10 yr old, not my 2 yr old, which is a more laid-back personality- thank GOODNESS!!)
Watch the body language instead of what they verbalize for your cues. When you ask them to do something or ask a question, etc., take a deep breath (quietly- don't heave a sigh :) and give her about 3 times as long to make that choice than you think it SHOULD take- without interrupting her or anything... just let her process it and let things sink in for a minute before you react to her. (Assuming she's not being physical, of course.) This has really been a lifesaver for me because it got to the point where I would just "assume" she was going to choose x when I wanted her to choose y, etc. and it was making it worse.
I hope this helps and doesn't sound judgmental at all. I was trying to take you on a little walk through my own experience. It's hard to be patient when your personality clashes with a 'stage' or a personality of your kids!!
M.