Please, I need your advice :(

My girlfriend and I have been together for over 3 years. In our future plans, we've talked about pursuing a Ph.D. together, looking for a common city or region and applying to 2 or 3 universities to at least have the chance of staying together at one of them.

Recently, through my former PI, a professor from a prestigious University contacted me to provide guidance in my field of work and discuss the possibility of pursuing a Ph.D. in her laboratory. The professor mentioned that my PI spoke highly of me, and she was pleased to have the opportunity to talk with me. I accepted the future meeting without informing my girlfriend, as I didn't think it was something that would worry her. After the meeting with the professor, I felt very happy. Not only is there a tangible possibility of working with her, but what she does in her laboratory aligns perfectly with my professional dreams. Additionally, the university's location offers excellent opportunities for personal and professional growth.

On that very day of the meeting, I shared with my partner the details of my conversation with the professor. Expressing my genuine interest in pursuing the Ph.D., I encouraged her to explore opportunities in the same region where the university is situated—which is one of the largest research parks, promising excellent possibilities for her as well. Deep down, I had hoped for my partner to share in my excitement and offer support, but unfortunately, that wasn't the case. She expressed her disappointment, mentioning that I had broken a promise we made. She said that the incident had impacted the mutual trust. I reassured her that considering this particular university didn't preclude us from exploring other regions together and looking into alternative universities. However, she remained firm in her stance, stating that I must turn down this opportunity in the situation she doesn't find something appealing in that specific region.

I acknowledge that it wasn't right to not discuss things with her earlier. However, I remain firm in my desire to be with her, and we can explore other places together. Nonetheless, I want to apply to this PhD and not miss this opportunity. What would you do? Would you risk losing a relationship? Should I reject this opportunity and look elsewhere with her?