<human>: Condense the text into a few key points

I am a middle-school english teacher and my fiancee is a software engineer. I love my job and cannot imagine a more rewarding (or tough!) job. 

We had a dinner party at our place today and we invited some close friends. We were having a good time and one of our friends said something about software engineering. I said "Yeah, she's a robot" clearly as a joke. My fiancee said "Well at least I'm not stupid" and it was obvious from her tone of voice that she wasn't joking. I asked her what she meant and she said "everyone knows those who can't do teach". 

It breaks my heart to hear her say that. To hear from her that she thinks I'm just a piece of worthless dumb trash who does grunt work because I'm too fucking stupid to do anything else. I've never felt more humiliated in my life.  

I left the room and she came after me and apologized, said what she said was out of line and that she was just joking around. Everyone knows she wasn't joking. We had a discussion that ended badly a few hours later where I blew up at her (i'm not proud of this) and she said I need to "get over what she said" and "I'm trying to make a big deal out of nothing". 

She's always been the more rational one and she makes me feel ashamed sometimes for being sensitive or for being emotional. I can't just "get over" what she said. It's not even that she called me worthless, it's that she legitimately thinks I am. I feel angry and humiliated and deeply hurt and I can't "get over it". 

We're not going to break up but I can't get over it. Her words have been ringing in my mind nonstop and it hurts like hell every single time. I don't know if I'm ever going to be able to forget it even if she was "just joking".
<bot>: Fiancee called me worthless in front of our friends because I'm a middle-school teacher and "those who can't do teach"