i cant focus on shit, and cant last doing a hard task without scrolling, its a severe problem that idk how to handle

A long time ago a was muslim too but after a while i came into a conclusion that this religion is no where near the truth, so became an atheist, i wanted to tell my muslim gf that iam an atheist and she gotta accept me as iam but iam afraid that she'll leave me and honestly, she treat me right and iam afraid that I'll never be able to experience that again, its heavy to hide this side of me but its even heavier thinking that she will leave me whenever i tell her that, i know its the right thing to tell her but i just can't, i don't know why Its just a cycle of endless pain