whats wrong with my goniurosaurus hainanensis

Hi to everyone i've just joined the forum and am need of some advice...
I have a pair of cave geckos m/f, i have had them 6 months now and they were doing really well but for the last 4 days my female has just not seamed right she is very lathargic and seams that even lifting her head is to much effort. i think she is eating although it is hard to catch either of them eating unless i sneak in middle of night. I dont think she has lost weight her tail may be ever so slightly thinner. the last few days i have put wax worms in a bowl which have been eaten but not sure by who. they have crickets which they are normally quite vicious about eating. the pair both have a few old scratchs on each other from mating scars as are vivacious. i dont relly want to seperate them as when i first got them it took them about a month to settle in and start eating as that was when i first found droppings. i keep tham on small repti bark they have two hides one a cave one a sheding cave they have plenty of places to hide and climb and i spray the viv so its humid. temps kept mid 70s daytime with drop at night. i've looked in books and on web but cant find any answers. Does anyone have any ideas please. thanks