Welcome to the forum.
A little more information about your glider would be helpful.
How old is she and has she always been alone? Gliders are colony animals and some just do not do well by themselves.
What feeding plan are you following? Are you following the staple recipe exactly as written? Are you feeding the fruits and vegetables recommended for the staple you have chosen to ensure the overall diet is well balanced and provides adequate protein, vitamins, and most importantly adequate calcium?
What WAS she fed for the 5 months that she did not get the "sugar glider food"? If you are referring to any type of pellet food as the main nutrient source in her diet - you may want to look at other feeding plans.
Pellet foods do not meet the nutritional needs of sugar gliders and may be difficult for them to digest well. Long term this could cause severe health issues.
I have links to a number of widely used feeding plans on my web page (left column) along with my own GliderKids Feeding Plan on my web page to help you locate information on these time tested diets that have kept gliders healthy for many years.
http://www.gliderkids-diet.com/Staple-Recipes.html
Being awake during the day could be a sign of illness. A vet check up would be a good idea if this has not already been done since she came back into your care.
Gliders do not drink much water - their fluid needs are met by the juicy fruits and vegetables offered each night along with a nectar like staple that meets their protein, vitamin and calcium needs.
Being awake during the day could also be due to the lighting situation in the area her cage is located. Gliders need light during normal daylight hours to cue their normal nocturnal sleep habits. If the room is dark during the daytime their sleep hours become irregular.
Gliders also need the room dark at night when they are supposed to be awake and active. If there are lights on late into the evening gliders may just stay in their pouch later and later - until the lights are turned off. My gliders are located in a sun room with windows on 3 walls. They are asleep before sun-up and wake up about half an hour after full sundown. If I leave a lamp on in the room they will not come out even if their food is in the cage until I have turned it off.
Once you are sure she is healthy, have her eating a well balanced diet and sleeping regularly during the day - please consider getting her a cage mate. Gliders are colony animals and really do best, and are more active, with a companion of their own kind.