For me, it wasn't. My family has been in New York city for well over 100 years... Irish heritage. From an early age i didn't buy the story of Christ, let alone the catholic thing.
I remember asking my grandmother - if Jesus knew he was god, then why is any aspect of the story impressive?
The best she could do was to tell me "its just important to believe" which of course just doesn't last. But she never raised her voice or made me feel unaccepted in anyway. I was about 10 at the time, and never gave the god question much thought until i was 23 or so. I was irreligious but believed there must be something... then i met a woman who commented "unless god means a timeless, disembodied creator of the universe, then you're just playing word games". Ive been an atheist since.
Despite the religiosity of my mother, and her mother, i didnt get much guff for my questions. And i never felt in anyway disadvantaged for not believing.
I'm privileged to be an atheist in NYC... its really not a big deal in my experience.
Whenever the subject comes up, i freely state my disbelief. My biggest interest is how anyone can believe, and as far as ive been able to figure, its a combination of wish thinking, tradition, lack of consideration, or fear of death.
I'd enjoy hearing about other people's experiences.
For me, the hardest part of being an atheist was the social isolation caused by being a disbeliever. Fortunately, I've learned to appreciate the quality of friends, not the quantity
I don't know if difficult is even the right descriptive. It was very convoluted for me while I was young. I didn't understand why the discrepancies didn't correlate and the people in my life that were old enough to tell me about it could never give me a description that I understood. So I took that as an admission of belief for the sake of belief. And I'm never wanted any part of that
It took awhile for me to except there was no god and religion is bs. When your family believes one sects way is the correct way to believe in fairy tales and closed minded about letting people of there family to explore another sect of christainity. Since, all sects of christainity are almost the same, why have anything to do with them at all. It's nice to think for myself and not to be held back silly guide lines.
I lost my faith when I started doing research. I started to practice questioning pre-existing assumptions to see what I thought and why I thought it. I wanted to be sure that there was evidence to support a position. The more I questioned my religious beliefs, the more it all fell away.
However, I started dropping away from being a catholic when I went to college and wasn't surrounded by the daily reaffirming messages I received in catholic school. I moved from a religion to a more deistic view that was more akin to a pagan notion of multiple gods (many paths, one mountain type of thing). I wasn't really ready to give up the idea of belief since it was so central to life in the US. I held on to that for a while until, well you already read the above.
I was pretty much raised atheist so no difficulty.