Cruentus
Grandmaster
The problem is I constantly want to do what ever I can to make her feel better...
I may be opening up a major time consuming dialog here, but I'll take the risk...
Looking at your quote above, I have to ask: What is YOUR motive with this girl? What need are you either getting satisfied or looking to get satisfied by dealing with this girl at all?
I ask because I highly doubt you're going to do what everyone is suggesting here (which are good suggestions, btw), otherwise, I don't think you would have posted. Even if you did what was suggested in this instance, I think that you risk repeating a similar error of involving yourself with a different dysfunctional person down the line.
I think that what you are looking for, really, is a way to continue interaction with this girl, thus to attain or persue whatever needs you perceive you have, yet also obtain a viable solution to the problems her friends and boyfriend pose with that continued interaction.
Therefore, if we find out what needs you're either getting or looking to get met by interacting with this person, then we will find the real answer to your problem. So, it would behoove you to sincerely think about the above question, and realize that your first answer may not be the actual or right one.