It must be terrible to go through life being convinced that everyone is out to get you, that everyone is out to cheat you, that everyone is out to take advantage of you. It makes life Oh so much harder than it needs to be.
And it makes being honest and standing on principle with someone who thinks that way oh so very hard. Because they are always convinced of the above, even when you are not remotely trying to cheat or mislead or take advantage.
The Tin Foil Hat Society 
I agree with you … such people are not easy to contend with. If it helps, the way I keep myself straight forward in such situations is to remind myself that doing anything else only validates their paranoid worldview. Either they will eventually come around and see reason, in which case they will come to appreciate your honesty; or they will never see reason, in which case there isn’t anything you could have done to please them anyway … and the only one who will understand your honesty under adverse conditions is you. I hope for you that the former will be the case; but also have an idea that in the end, it is important to you to remain honest … not necessarily a solution so much as a solace.
Ah. But it’s not everyone… It’s, unfortunately, far too many though.
Sounds like my ex.
It is hard to relate and communicate with people like that.
Oh, you met my ex… sorry. Just exhausting, huh.