I felt the same as you in a relationship I recently ended "I feel I will never truly know him and that he will never truly be honest". How long have you been with this man? I was with mine for almost 5 years and he never opened up to me, would give me a little bit here and there and I caught him in multiple lies. It tore me up inside and caused me so much anxiety and pain. I had to finally leave once and for all for my own piece of mind. It was one of the hardest things I've ever done, because I loved him, but I had to save myself from the misery and deceit. If you've been with him long enough where you think he should be more open and honest with you, my opinion is that he never will be and you should think about what's best for you. Good Luck!