Yeah bofs right. Reading is something that you develop a lot better with a teacher. Sight reading IS important, if you want to be a musician, or even if you want to get together and jam with friends, it helps so much to know the language of music.
Also, learning songs, you can do it on your own. It's things like reading, theory, improvisation, excercises, that you are more likely to get better at if you have a teacher.