Because you do not know how to speak properly
That would be the only reason I would know. Other wise you need a new girlfriend.
because shes testing to know that how much strong you are
You allow them.
Because you let her make you mad.
Because you have anger issues?
Lol. because you do not cook for her. :-)
She's a girl?
Because female's & male's don't understand each other, the truth be know you get her mad too