She is unhappy about something, my gray tree frogs have only burrowed once and it was when the temperatures in my tank dropped way too low once. Do you have something to monitor the temps and humidity? What is the size comparison between the frogs...female gray tree frogs will eat almost anything that moves. So if the male is too small, she could definitely eat him. That being said, I do house a female over 3 inches with a male that is only 1.5 inches without any issue.
If you can fill this out, it would really help us help you figure out what is going on -
1-size of enclosure
2-# on inhabitants - specifically ( if there is another frog ---size differences ?)
3-humidity
4-temp
5-water - type - for both misting and soaking dish
6-materials used for substrate
7-enclosure set up i.e. plants( live or artificial) wood, bark etc -how were things prepared prior to being put into the viv
8-main food source
9-vitamins and calcium ? ( how often )
10-lighting
11-what is, specifically, being used to maintain the temperature of the enclosure
12-when is the last time he ate
13-have you found poop lately
14-a pic would be great ( including the frog ) any little cell phone pic is fine
15- how old is the frog
16-how long have you owned him
17- is the frog wild caught or captive bred
18- frog food- how often and if its diverse what other feeders are used as treats
19- about how often the frog is handled
20-is the enclosure is kept in a high or low traffic area