My adhd partner lies

Looking for advice on how to stop an adhd husband from lying to cover up things he is ashamed of.  I just got back from a vacation without my husband and saw a couple of new scratches on his brand new truck.  I didn’t say anything about that for a couple days and then asked him what happened.  He said those scratches were there since the winter and that I just never saw them.  I park by his truck everyday.  I know he is lying. He does this occasionally and then tells me I’m a terrible wife for not believing him.  I feel like he is playing mind games woth me.  Any recommendations on how to solve this marriage  problem would be comforting.