My question is are you struggling with honesty or exact wording. I try to be as honest as I can (excluding the "I'm fine." when I feel like crap comment at work and other polite lieing) I try to word things as accurately as possible but you said that you are aware of it "every second of the day" and that you form the words in your mind ahead of time to make sure that they are true. We all mispeak sometimes. I remember in college, I advertised something as starting at midnight. Then they served the pizza earlier so that the people who waited until midnight didn't get any pizza. I felt guilty as if I had lied.
So, my comment would be that if you say something that you think is true then you are not lieing. My second comment is that God will forgive you for lieing if you are trying your best not to lie. I suspect that it pains God's heart to see you struggle so much to avoid lieing even unintentionally. I hope you find a way to deal/cope with this issue.