I used to wrestle with these questions, as well, but have concluded that there is such a thing as "facts based on scientific fact" and there is a genuine, honest discovery process using science to uncover more facts, develop understanding and to change when we discover we're wrong. I am not a simple materialist so as for the other questions (purpose, meaning, morals, ethics, God, afterlife, salvation, etc.) Humanity will continue to make up any and all answers and theories that suit them at the time for purposes of comfort and assurance and so on. That's religion, for the most part, and a few other things like philosophy, patriotism, tribalism, romance, fantasy and so on. By the way, you are mistaken about Einstein. It's a common myth but it's not true.