Need some advice please (red tailed boa)

[spence198111]

Hi all,
Hopeing someone can give me some advice please.
I have a red tailed boa, female and around 5,8, she's always been brilliant great manor and always feeds well she ads have been great, but in the last 5/6 weeks she's become very aggressive always hissing and striking at me also gone of her food, I have no idea why she has started to act like this as I've never had any problems with her but now it's nearly impossible to handle her.
Any advice would be great