talk (oneself) out of (something)
1. To fail to earn, receive, or achieve something because one says something foolish, troublesome, or discrediting. He had a really impressive résumé, but he talked himself out of the job during the interview. She talked herself out of the promotion when she started discussing her desire to try working in a different industry.
2. To convince oneself not to do, try, accept, receive, etc., something. I had a really good job opportunity in London, but I was so nervous about moving to a different country that I talked myself out of taking it. It's like she's determined to talk herself out of happiness.