When I take the Big 5 personality test, I generally score below the 10th percentile in neuroticism (basically a measure of emotional fluctuation and propensity for negative emotion), whereas when I answer the questions as if I was my girlfriend, it comes out showing she is above the 90th percentile. This is a very large difference in our personalities. On one hand it creates problems, but on the other hand it's almost a necessary evil because nobody who was emotional would be able to tolerate my gf's moodiness[/quote]
More free advice from me:
Just the fact that you both took a personality test shows that you are both well aware of your differences. The test results confirm the differences. Why do you feel it is a "necessary evil"? Or better put, why do you need evil in your life? It is not necessary. Run away at your next opportunity.
The break up will be easy. Next time she blows up over something minor, break up with her. It will be just cause, aka, not your fault. This time, do NOT go back.