Things & friendships definatly change in sobriety like you said you have become goal focused which isnt a bad thing if your starting to get bored because its diffrent now that your sober im not saying your friends are boring but it just isnt you anymore
if your losing friends for diffrent reasons as long as its amicle i dont see the harm things change so do ppl
have you still got friends that are keepers i have a solid smalll set of friends in my real life that il stay in touch with for life not unless things change which they sometimes do
im sure youl make new friends along the way