Awe I’m sorry to hear this 😫😢 it’s soo horrible to have and it’s very brave of you to even ask for advice… definitely see a therapist even a private one not NHS! I’m 23 now I’ve had a stutter since I was 5 it’s improved but I still have it! Just keep practising everyday.. YES it’s mentally draining tho it has to be done :( let your friends and family know for extra support 💚 you’ve got this🙏🏻