Why my 2,5 years old doesn't sleep at night and wants her bottle.?

Sorry but there will be no easy solution to this. You just have to stop giving her the bottle. Once the decision is made, be consistent and don't back down or give in, because as soon as you do, she will realise that she can do something that will get you to change your mind. Unfortunately doing this is going to be difficult and will result in her crying and you getting a disrupted sleep, but hopefully it won't be for too long. Good luck