We feel happy or we do not, it is neither truth nor lie, it is a feeling.

Depends on what the lie and the truth are, specifically. I believe in a kind of idealistic monism or solipsism.

Reality. Every time. It's my programming

Knowing the reality that makes you miserable allows you to change your circumstances (or attitude) to alleviate the misery. Then you have happiness, by taking matters into your own hands.

If you know it's a lie, how can you do that? Or do you mean living a lie , but you don't know it's a lie? Anyway, reality is always there, no matter what you try to do to elude it. I'm not sure if I can answer this question.

A miserable fact is always preferable than a happy lie. Because that's the only sustainable way to live.

Sad reality. I don't think I have a choice though, Im too neurotic to have ever had a chance to experiment with blissful ignorance. Even when I was ignorant and completely sold on faith I wasnt blissful. Slightly reassured by illusion maybe but once you know that, then its a relief to be optimistic about real possibilities and taking personal responsibility. Those offer real advantages because theres a tangible version of karma at work. Knowing that cause and effect is the only intercessor on our behalf empowers us to take control of the future by consciously building it for ourselves.

If living a lie makes you happy go for it. I am just not good at doing that.