My wife did that a lot while we were dating, Leritzi. It took many years, but my extreme sarcasm eventually broke the from her. My suggestion is to tell her (when she's not in this mood, mind you) that what she does really bothers you and that you're going to have to do something different because you don't like it when she does that. Tell her you want to be supportive, but she can't treat you like that. Ask her if she has suggestions on what you can do. She'll either come to terms with her behavior, she'll suggest something useful - like leaving for a while, or she won't respect you enough to want to change.
Fortunately, my wife turned out to be pretty resiliant because when she did that to me, I'd just stare at her and not say anything until she got mad at me, or I'd tell her that she sounds just like her mom or something else I knew would push her buttons. A lot of it is that she wanted to pick a fight. I found it was best to fight on my terms about nonsensical things.
