Man, my girlfriends always acted similar when I brought up my stuttering and how it was making me feel. They never helped and told simply told me "no one cares about it" Clearly that's a lie and isnt always true, despite that it always affects your interactions with people. I wouldnt be so isolated and for so long, hell descriminated and out of a career if people simply "didnt care" and "it's in my head" Bro, you are cold dude and need to adjust how you are reacting towards her over it. I get your point only to a slight degree, you are completely writing off the true pain and deeply debilitating condition she has to endure with everyday in every social situation. Empower her and make her feel proud of herself for getting through situations. Let her know she is strong instead of gaslighting her. Perhaps you mean well, but I have had many friends like you who have said similar things to me. Yet, they made fun of my stuttering, laughed at it at times, and they never really respected me in the first place. I am extremely isolated and I really did do my all. I threw myself into social situations, clubs, and jobs. 31, completely isolated, little to no friends, descriminated from jobs, have trouble keeping a job and when I do they easily forget about me. Obviously, it is not as simple as "no one cares, omg it's in your head" CHANGE your attitude towards it and help her, stop invalidating her.