I think more information may help. You're not obliged to answer all these questions, but -
Are you something like a digital nomad, or do you have a job that sends you off to travel frequently? Does your girlfriend accompany you wherever you go? Is she working at all at the moment? What are your priorities, and how much are you willing to compromise? How badly do you want to spend the rest of your life with her? The money that allows you to be FIRE in 4 years, does that cover only you as an individual or both of you as a couple, or in other words, do you have her covered financially if she follows you and hinders her own career path as a result?