Bottle help!

So my 7 1/2 months old doesn't drink her milk from the bottle anymore! She stopped a couple weeks ago. I thought because she was sick. Then she was over that and still not drinking, so we thought it was the nipple, got the next size, and still nothing! She just bites it. She nurses fine and she has been fine on the bottle until a couple weeks ago. She also eats her food nicely. We've been using the milk to mix with her cereal so it gets used and she still gets the benefits, but I'm very frustrated. Any suggestions as to why she won't take the bottle anymore? Thank you!!