I [32M] feel like I'm not permitted to express any negative emotions when I’m talking to my girlfriend [30F].

My girlfriend and I both work for the same company, but in different regions. She is currently applying for a Vice President position on our national Board of Directors, while I am seeking a Director role for a remote position overseas. Throughout this process, I’ve noticed that whenever I'm feeling down or stressed, she becomes very judgmental and seems to lack understanding of my perspective. When I express my feelings of stress or sadness, she often starts crying, and I find that seeing her upset affects me deeply, often leaving me feeling guilty. It seems that in this relationship, I am discouraged from expressing negative emotions. While I recognize the saying "be a man and tough it up," that doesn't resonate with who I truly am. I want to be open about my stress and share my feelings with her. How should I approach this situation?