Interesting thread. I actually grew up atheist, became a “born again” evangelical in my 20s, and made my way to the Catholic Church at age 60. Every person needs to, in some way, detach from their upbringing and ask honest questions about the way they were raised. Thanks for your genuine concerns.
It’s easy to get emotional about religion and we need to detach from that as well. But the main thing is, in addition to honesty, to answer with love and empathy to the other person. Wouldn’t you agree that, atheist or not, love is the highest human value? Humans need HOPE and LOVE, and this doesn’t have to mean lying to one another. We also need FAITH, not necessarily in God, but, for instance, in marriage, so that we don’t have to spend a lot of time worrying about the “what ifs.” You need a certain amount of faith just to get up in the morning and plan your day.
I’m glad that you don’t seem like a bitter type of atheist. If you anticipate that others will become bitter towards you, just focus on love and honesty. (I like the Christian concept of “conquering with love.”) You might think about writing down statements that they make that trouble you and then later, in a detached way, mull over them to determine what is true and what is false. You might actually be doing your relatives a favor by challenging them to think more clearly.
I’d be interested in knowing where you think love comes from, since it is invisible. Don’t things exist that are invisible, like the wind? Why does something exist instead of nothing? Where does beauty come from, and the amazing patterns and designs of nature? Also, do you believe in free will?
Wishing you the best.