my husband has almost 5 years of sobriety and his default mode still is to lie - about STUPID stuff even. He lived his entire life that way and it was just the way he rolled. He strives to be more honest but it certainly isn't something that comes naturally to him. I want to trust him completely but he hasn't earned that right at this point.
Trust is earned and not given. No amount of understanding of "why" someone lies will change the reality of the lie. I can live around my husband but there are still a whole lot of things that I don't trust him with yet - namely my heart.