I have never been in a situation similar to yours, so my advice may be wrong, but here it is anyway.
When people change their opinion, they sometimes go from one extreme to the opposite extreme, as if to make sure they would not drift back to their old position. But there is no need for sudden large changes. Unlike religious people, atheists do not have a duty to proselytize everyone to their non-belief. To put it bluntly, you are allowed to lie and deceive, if it is necessary for your survival. I do not support lying in general, because it has its cost, but sometimes telling the truth (at the wrong moment) has a much greater cost. The cost of lying is weakening the relationship with people you lie to. So I think you should try to be open with your wife (but be careful about your coming out), but lying to everyone else is an option.
When explaining how you feel, focus on the positive parts, not the negative parts. Rejecting religion is the negative part. It is not your terminal value to be non-religious. You probably still like some aspects of the religious culture; and that’s okay. (Atheists are free to celebrate Christmas, if they choose to.) It’s just that your positive values are understanding the world, being honest, etc. and religion happens to be incompatible with that. You are throwing religion away because the alternative would be throwing your curiosity or sanity away. If you are going to explain to someone the negative part, you should explain the positive part first (without even mentioning religion at the beginning). Only when they value the positive part, you should show them the conflict; then they may empathise.
Specifically, I think you should show your wife all the cool things you are interested in, starting with the noncontroversial ones. She does not have to like them all; different people have different preferences; but you may find something that is interesting for both of you. Then you have an enjoyable topic to talk about which is unconnected to religion. The more such topics you have, and the more time you spend debating them, the less time you spend debating religion, and the less role the religion plays at keeping you together. Then the impact of abandoning religion will be smaller. Just start with the simple stuff; do not go into “adversarial intellectual debate mode” you are probably using with your friends sometimes. Instead, be a guide in an intellectual adventure. For example, find some noncontroversial TED talks videos (not about religion, politics, evolution, global warming, or whichever topics are controversial in your religious community) and watch them together (maybe even with your children). Be the one who brings positive value, not the one who causes conflict.
You should be strategic about your social circle. I do not know the people around you, but I have read stories where people lost their whole religious community after coming out. You may have a few loyal friends who will stay with you regardless, but even those friends may be under pressure from their friends and families. You prepare strategically for this by creating new friends in advance. Preferably ones that your wife will like too. Every new friend who does not share your religion, is a friend who will not abandon you when you come out. To some degree, friendship is a question of spending time together, and having experiences in common. Essentially, you should manage your time to spend more time with people outside your religious community. (I hope they are available.) Again, bringing new nice people as friends is a positive step. Finding new interesting activities you and your wife could enjoy together, outside of your religious community, is also a positive step. You could take a family vacation outside of your community, with the new friends.
Shortly, build new bridges before you burn down the old ones. Treat everything related to your religious community as something you may lose, as something that may be used to blackmail you in the future, so do not invest in those things. Plan to minimize possible damage in the future.
Also, if you want your wife to support you, you also have to support her. Support her in all her dreams, help her explore the world. Be a team together. Make it obvious you would support her even where your religious community wouldn’t.
Specifically, I think you should show your wife all the cool things you are interested in, starting with the noncontroversial ones.
Assuming that you don’t already do this, doing this signals “I am trying to convince you of something which I don’t want to talk about”. People notice when you act in ways that you haven’t before.
I have never been in a situation similar to yours, so my advice may be wrong, but here it is anyway.
When people change their opinion, they sometimes go from one extreme to the opposite extreme, as if to make sure they would not drift back to their old position. But there is no need for sudden large changes. Unlike religious people, atheists do not have a duty to proselytize everyone to their non-belief. To put it bluntly, you are allowed to lie and deceive, if it is necessary for your survival. I do not support lying in general, because it has its cost, but sometimes telling the truth (at the wrong moment) has a much greater cost. The cost of lying is weakening the relationship with people you lie to. So I think you should try to be open with your wife (but be careful about your coming out), but lying to everyone else is an option.
When explaining how you feel, focus on the positive parts, not the negative parts. Rejecting religion is the negative part. It is not your terminal value to be non-religious. You probably still like some aspects of the religious culture; and that’s okay. (Atheists are free to celebrate Christmas, if they choose to.) It’s just that your positive values are understanding the world, being honest, etc. and religion happens to be incompatible with that. You are throwing religion away because the alternative would be throwing your curiosity or sanity away. If you are going to explain to someone the negative part, you should explain the positive part first (without even mentioning religion at the beginning). Only when they value the positive part, you should show them the conflict; then they may empathise.
Specifically, I think you should show your wife all the cool things you are interested in, starting with the noncontroversial ones. She does not have to like them all; different people have different preferences; but you may find something that is interesting for both of you. Then you have an enjoyable topic to talk about which is unconnected to religion. The more such topics you have, and the more time you spend debating them, the less time you spend debating religion, and the less role the religion plays at keeping you together. Then the impact of abandoning religion will be smaller. Just start with the simple stuff; do not go into “adversarial intellectual debate mode” you are probably using with your friends sometimes. Instead, be a guide in an intellectual adventure. For example, find some noncontroversial TED talks videos (not about religion, politics, evolution, global warming, or whichever topics are controversial in your religious community) and watch them together (maybe even with your children). Be the one who brings positive value, not the one who causes conflict.
You should be strategic about your social circle. I do not know the people around you, but I have read stories where people lost their whole religious community after coming out. You may have a few loyal friends who will stay with you regardless, but even those friends may be under pressure from their friends and families. You prepare strategically for this by creating new friends in advance. Preferably ones that your wife will like too. Every new friend who does not share your religion, is a friend who will not abandon you when you come out. To some degree, friendship is a question of spending time together, and having experiences in common. Essentially, you should manage your time to spend more time with people outside your religious community. (I hope they are available.) Again, bringing new nice people as friends is a positive step. Finding new interesting activities you and your wife could enjoy together, outside of your religious community, is also a positive step. You could take a family vacation outside of your community, with the new friends.
Shortly, build new bridges before you burn down the old ones. Treat everything related to your religious community as something you may lose, as something that may be used to blackmail you in the future, so do not invest in those things. Plan to minimize possible damage in the future.
Also, if you want your wife to support you, you also have to support her. Support her in all her dreams, help her explore the world. Be a team together. Make it obvious you would support her even where your religious community wouldn’t.
Assuming that you don’t already do this, doing this signals “I am trying to convince you of something which I don’t want to talk about”. People notice when you act in ways that you haven’t before.