You're blaming yourself and taking responsibility for a lot that is beyond your control. You are not responsible for her life. She is completely in control of what happens to her life. I know you're probably thinking of all the 'buts' because you know that you have helped her and you do care and don't want to see anything bad happen to her. But what SHE chooses to do is beyond your control. Seriously.
You know that you don't want to be in the relationship right now. It isn't fair to you and it isn't fair to her because you know that it isn't what you want anymore. She deserves to be with someone who wants to be with her completely and that isn't how you feel anymore. You also can't sacrifice your own happiness for someone else. This is your life. It's your chance to find what you're looking for and someone who makes you happy and complete. It sounds incredibly selfish. But it's also true an I think you see that.
Ending a long relationship is never easy and your situation is more complicated because of her emotional instability. But it seems inevitable at this point. Do you think it will help her to drag it out for longer? She certainly deserves the respect of having you be honest with her about how you feel. And the respect of having you end it before you guys waste longer in a relationship that you know is pretty much dead already.
I would suggest making sure she knows that you're serious about wanting to remain friends. Tell her that it isn't just a break up line, you really have valued her friendship and hope she'll stay close with you. And then let her know that you want to see her do great things with her life and fall in love with someone else. I just feel like reminding her of the good in her future will help her see it instead of dwelling on the pain that comes along with ending a relationship.
By offering her your continued friendship and then following through by making sure you really do talk to her after the break up, you're doing all that you can to protect her while also giving yourself a chance to be happy and fall in love. Her life is not your responsibility. She is responsible for it. As much as you're tempted to sacrifice yourself for her, you also know it isn't what is right for both of you. Really, she has to grow and learn to stand on her own.
Sorry you're in such a tough spot, Ryan. If you ever want to talk, just drop me a line. <3
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kid, I wrote back,
all lovers betray.