I know several people who claim to be atheists. They are perfectly fine and sane people, law abiding and as friendly as anyone you would care to meet. In fact if they have a single flaw it is calling themselves atheists. Several of them were devout Christians as youths, even to the point of proselytizing in public, but at some point the assertion of non-provable ideas against other ideas which had some real-world testability made them swing away from traditional faith-based religion toward testable science-based ways of relating to the world.
Personally, I never had these conflicts because I grew up accepting the world to be as I perceived it to be. Of course there were things I didn’t know, and never would know. Perhaps there were things which simply could never be known, like life in distant galaxies, but that didn’t bother me; it was simply unknowable but it was unlikely to affect me, so why worry. The great questions like the disappearance of consciousness with the disappearance of the body just seemed obvious, and I never had any longing for a physical after-life. It struck me like trying to teleport to that distant galaxy where nothing familiar to me would be, even if I were in a place habitable by my body. This is Earth, this is where I am, this is what my body is adapted to and this is the environment to which my mind and personality are now fitted. Why should I wish to go somewhere where nothing about me, as I am, would fit or work very well? It is challenging enough to make things work where I am adapted; in fact it is just the right degree of challenging to make everything here interesting.
Proclaiming publicly to be an atheist seems foolish to me, because it doesn’t make any difference to one’s self the term one applies to one’s self, or to the relationship one claims to have with the world. However, it does make a difference to other people what you claim to be relative to those other people. The term atheist means you don’t believe in something which most of those other people do believe in. You are challenging the fundamental beliefs upon which they construct their personal reality. You are declaring that what they hold most valuable to be foolish, and to that large majority of people you are setting yourself to be their deadly enemy. Being a deadly enemy means that they will choose to kill you when the circumstances are permissive. Life is difficult enough without seeking to be killed by more than half of humanity. Besides, it is totally unnecessary too, and foolish, and will not change anyone for the better even if you were successful, and nearly always it will change your relationship with those people for the worse.
Even the most devout theists have moments of doubt. Even Mother Teresa, who got a Nobel Peace Prize for her good works, had the most profound of doubts. Calling yourself an atheist only serves to make yourself into a self-proclaimed devil in the eyes of those people, and this is especially painful for those theists when they happen themselves to be momentarily in the throes of religious doubt. The atheist will get no respect or love from those people burning with doubts; they will get burning hatred. With those believers in a more ordinary state of ongoing belief, they will get a more mild form of hatred. All the same it will be hatred and it is a hatred constrained in performance only by conformity to the laws of their state against homicide.
It seems more reasonable to accept people as they are and not as you think they should be. There are some seven billion of them now, and it is unlikely you are going to affect the religious beliefs of many of them, actually a single one of them, by your challenges to their fundamental beliefs. A better approach is to make clear the workings of the natural world we find around us. It is amazing enough and offers plenty of things to which we are well attuned to live with.
Our task, should we choose to accept it, is to live in this world and help others to do so to.