Your problem is husbandry related, small insecure snake will tend not to eat.

Here is what I would do

Move your BP to a 6 quarts tub - 15 quarts at the very most
Offer 1 or 2 hides (depending on the size of the tub) use 6 inches plastic plot saucers
Use aspen bedding
Provide a hot spot of 88 degrees (measure with a digital thermometer) and a cold spot of 76/78 degrees
Move your BP and wait a week before offering a live small mouse.

In the mean time not handling until your BP is a consistent feeder.