What's in the bottle? If it's milk I would stop it, change the routine so she has milk before bed then do stories etc and clean teeth then put her to bed without the bottle.
You will have a few difficult nights because breaking props with a toddler is never easy but I feel cold turkey is the best way. If it is milk in the bottle it will cause problems for her teeth if she is drinking it during the night and she doesn't need it for calories or nutrition at this age.
How is her routine in the day - does she still nap? Does she go for her nap with a bottle?
Laura