Sever stutter only around my mom

Sever stutter only around my mom Little backstory: my mom has been the most supportive person of my stutter. Yet I stutter the most when I’m talking to her. I have an occasional stutter when talking to others. Or sometimes I don’t at all. Can anyone explain this. It feels horrible because I can’t remember the last time I had a real genuine conversation with my mom about anything besides mandatory things. I don’t want to go my whole life without being able to talk to my mom.