Maybe talk to her family to see if she can get help. There is obviously something going on that may be serious. She needs to realize that if she wants the relationship to work, she needs to listen to you. Her saying that she might as well die is not healthy in a relationship, and I'd advise you to be careful with what you do/say, especially since you don't know if she was serious or not. Consider having her see a counselor, if she's not willing to talk to you about these problems. In my opinion, when someone is clingy in a relationship, it means they have some sort of self-esteem issues. And if she wont see a counselor, maybe you should. I'm not saying you have any problems, but seeking professional advice on how to deal with this may be a good idea, if nothing else seems to work.
Hope this helps
