My 3yo always shouts "I don't like you" whenever she is angry or not getting what she wants. I know she doesn't mean it but it can be demoralizing at times. Does it happen to you too, and how do you deal with it?

You might want to spend some time to reconnect with your child to understand what is the underlying issue. You can do some role play with her using two little dolls and act it out. I noticed my girl (3.5 years old) behave badly when she need a good cry or laugh due to some issue in school. For example, teacher tell her she is naughty as she never finish her food although she is full or she got bully by classmate. They acts out what they experience as they are not able to explain how they feel at this age.