First of all, I'm still a newbie aswell, but I will try and help as much as I can
What it seems to me that she is doing, is using you as "an emotional tampoon". She tells you all her worries, and you listen and comfort her. The single most important thing you are doing wrong, is that you need to raise your value. YOU have to be the prize, so that she won't bother you with things like that. For example, you can try and raise your value by not being available too often. When she calls you just say "Sorry, I'm busy and can't talk right now." By doing this, you will get her more interested in you, because she thinks she's not that big a deal for you.
What this COULD result in however, is that she will completley stop talking to you, because you no longer satyfies her. If this happens, I would guess that she has a couple of other guys just like you. Waiting for her to say frog so they can jump.
As said earlier on, I'm still a noob so I'm open for correction by others on my theory, hell, I might even have misunderstood your whole post

But atleast this is my perception of what's going on! I hope this was of any help to you!
- The Dice