Originally Posted by
haxartus
The first time she started to insult you, you should have been like "Fuck you, get out" (unless you did something really bad and you deserved it).
After you let her insult you for no reason, she basically lost all respect for you. Women can't be attracted to people they have no respect to, so she is probably also cheating on you.
Mentally she is thinking of reasons why you deserve to be cheated to justify it to herself (people need to feel good about things they do), and then gets angry at you about the "reasons".
She also wants to avoid things that makes her look bad, like dumping you or you finding out about the cheating and confronting her. So she probably prefers that you dump her (without finding out), hence the weird behavior that is intended to lead you to the decision.
This is all very basic stuff and you should know it.