Take it slow, learn about healthy boundaries&let her have her space. I've known many people like this who start out inviting me to everything they do, call frequently&e-mail frequently only to have them totally back off because I expected more than they were able to give. I've remained "friends" with many of these people, but I refer to them as fair weather friends. Sometimes it's hard to understand people who don't follow your lead in relationships. (i.e. spilling your guts to them only to have them tell you that you depress them or they never spill their guts to you.) Good, solid,lasting friendships are hard to come by-so hang in there&if she's really the good friend you see her as, she'll open up to you too.