3 (almost 4 year old) bedtime trouble.. Advice?

My 3 year old acts like bed time is the end of the world. She throws the biggest fits, ends up getting out of bed tons of times, tries, would and has stayed up passed midnight. She will get up saying she's thirsty, needs a snack and the ones that really get me is her crying saying I want to cuddle Mommy and I usually give in to that one and let her lay with me. When I don't give in she lays In bed loudly crying.. She gets up and comes in our room and usually ends up waking her 3 month old sister. She said she was scared of the dark so I leave the lamp on, she said she didnt like her door closed so I leave it cracked open. When I make her lay in her bed and she actually falls asleep it's because she cried herself to sleep. Or I can start trying to get her to calm down and in bed at 8 and she will not end up falling asleep till around midnight. She will be 4 in January. Anyone have any tips and advice?