Fasting is presented as the holy grail that will cure it all. The reality is that fasting isn't for everyone and that it can trigger disordered eating and binging.
If you struggle to fast, don't. What would you like to achieve by fasting?
You can and should however tackle the snacking and understand that an adult woman doesn't need to eat between meals and that a lot has to be with associative behaviour, like being used to eat in front of tv or while MNetting.
You need to break the snacking and all the specific moments associated with it, and you should not only bin all the rubbish you have in the house but also understand that if you maintain the habit eating a healthy snack such as a carrot, the need of snaking will never go away and one day before you know it, it will be back to the crips or whatever your devil is.
UK is so addicted to snacks and it is not your fault, this behaviour start from babies, when mothers are encouraged to give their not-even 1 year old snack such as puffs, rice cakes, cereal bars and it continue in childhood with daily crisps or chocolate or whatever.
I am French and I don't know a single adult woman who snacks in France . It is culture and behaviour and it is in your power to change that.
So focus for now on what is in your power, and that is what you buy instead of fighting a vital instinct of eating to enforce fasting.
Good luck!