She always brings a friend, yet she seems really into me. What does this mean?

Well she does appear to like you. Her bringing friends along is probably her way to combat nerves. When you like someone and they like you back there's pressure to make your 'date' work. That third person there just puts ease on the whole thing and helps avoid awkward silences. She may also be feeling indecisive as to how far she wants to take things, her simply liking you and wanting an eventual relationship with you are two different things. Remember who tagged along though; two family members and a close guy friend! Those are the people who care about her most! She could really think your special and brought those important people along just to seek their approval on you because YOU could be 'for keeps'