I cannot tell you to stay or leave, but I can say it's sometimes hard on both people when there are frequent breakups. For some couples that isn't as big a deal, or as big a strain, and it can even help them work well together in a way I don't quite understand. She may crave the excitement here, or there might be something else going on, so the question is are you content with the current dynamic? And the other question is, do you enjoy the relationship even though this happens or do you enjoy it enough that you want to try and make it work?
A couple ideas, if you decide you want to try to make things work with her.
* Try going here (if it will let me share the link) -
http://www.nonviolentcommunication.com/aboutnvc/4partprocess.htm - and use this model, both of you, to solve the next issue. Ask her to follow the four steps and you do the same. It is designed to keep people from speaking defensively.
* Ask her to speak only in "I" statements and you do the same. Not "you never call me when you're away from home" but "I get upset when I don't hear from you all day."
* Say the things she tells you in your own words, each time she makes a comment. This will show her you're listening.
You could also try, next time she starts a heated discussion, asking her what she needs from you. How you can fix it.
Oh, and if she seems to thrive on lots of stimulation and excitement and risky situations, or new situations, then if you enjoy being with her aside from this pattern, you could try to meet that need by taking her out to new places or traveling or some other thing that helps her get that excitement feeling without creating conflict.
