She is striking as defensive behaviour as the mouse may be to big. When you leave her alone she will relise its fine and eat it. I had the same problem with my pied spider male and I just put the mouse in her enclosure and she released it was fine and ate it, eventually she released there was nothin to b scared of and just ate it normally. If you put it in her enclosure though, remember to take her out, maybe to another room, put it in, and then put her in cause otherwise next time u hold her she will expect food coming in so she may strike