Some have accepted it, some haven't. It really doesn't matter to me
whether they accept it or not. It doesn't have anything to do with them.
As far as the "approach" went, I was honest and completely upfront about it.
It was during a family get-together and several were discussing going to mass the next morning. I was asked to go along, and I said "no, thank you".
They pressed, I told them I'm an atheist.
I think my exact words were, "I'm an unapologetic atheist."
That was a fun evening.

I've really only told them that I'm seriously questioning (Bible, God, Christianity, etc.). In-laws took it with a little sadness. My Mom got very emotional. Dad was more muted. My wife actually knows where I'm at and is devastated. It's pretty shitty. Deconversion isn't fun. But life is interesting in so many new ways; I wouldn't trade the pain for an illusion.

I was pretty agnostic when I married my wife and by the time I figured out I was in fact atheist we had an about 8 year old daughter. My wife had her go to catechism for a couple of years when my daughter decided it was nonsense and asked me what to tell her Mom. I told her to be honest and my wife just said OK. My daughter didn't take long to decide she was an atheist also and told her friends at school. As far as I know it was never a problem there even though all of her friends were very religious.

I never felt it was some thing I had to 'announce'. When I was in my teens, while having a conversation with my mother a couple of years after my grandmother died (who was a very devout Catholic), I casually stated, "well, maybe there is no God, after all, ..." and before I got any further, my mother stopped me. She was incredulous, and asked how I could possibly say something like that. So I gently tried to explain,and somehow got my point across. I think because I never pushed it with my family and I attended weddings and other events, even though I didn't participate in Mass, she was able to accept my feelings.
I've even been asked to give eulogies for some of my family members, but have managed to speak without ever making any religious reference whatever and keeping all true to the purpose of the day.

I just kind of blurted it out one day in front of my mom and dad when I was home from college. I had told my dad 1-2 years before that I didn't believe in God; I guess he thought I was still trying to figure things out at that time. Normally, my parents tell each other everything, so I thought he had told her. Well, when I blurted it out, my mom looked very surprised.

I looked at my dad and thought, "You didn't tell her?"
My mom noticed this and looked at my dad and said, "You knew?"
My dad said something along the line of "I kind of knew something but I didn't know it had gone this far."

My dad then made a stupid comment that atheism was one step closer to becoming a Satanist. Completely dumbfounded by what I just heard, I exclaimed, "What? No!"

My mom then calmed everyone down and asked me to explain what atheism was. We had 1-2 more talks about my beliefs down the road, but my dad has never truly accepted me being an atheist. I never actually told my two brothers (older and younger), I think they just found out through posts from Facebook or maybe my parents told them. My older brother will send me funny stuff about atheism. My younger brother has never brought it up.