Unfortunately, it's not as easy as it sounds. It's hard because it will require most of us to change our characters. If you are someone who is a perfectionist, extremely hard to please. You will have a tough time having a healthy relationship with your spouse, if you decide to be honest always. The only way out is to stop being a perfectionist.
Sadly, I'm not always honest. I'm always acting like I'm enjoying a boring conversation; but deep inside of me I won't mind a catastrophe happening to interrupt the conversation. I occasionally smile to ensure the disgust I'm feeling inside does not show on my face. I say thanks a lot of times when I don't mean it. And then there are the ones I'm really ashamed to talk about.
My aim is obviously not to show you how to be honest at all times. I'm not qualified to do that. My aim is to show you that honesty is truly the best policy. I have never regretted any moment I have been completely honest. Sincerely, I do feel sad once in a while after taking a honest action. I also frequently get criticized. But after sometime, I always realize that it was the best decision.
When you're honest, you're being true not just to others but also to yourself. When you are honest, you're doing the right thing. It may not be the most beneficial thing. You may be hastening someone's judgement/punishment or revealing secrets. But they will be well deserved judgement and secrets that shouldn't have existed in the first place.
Honesty is not an act, it's a way of life. It will require you to discover your true self and make hard changes. Because you will always be truthful, you will not want to be a part of a scheme that is shady. You will not want to keep a habit that you're not happy admitting. You will not want to keep friends that keep putting you in embarrassing situations. You will be extremely responsible, dependable and a man of verifiable integrity. The kind of person everyone wants to have important deals with. Even the people that complain about your frankness will be proud to know you and always willing to vouch for you. You will not have trouble getting anything from (almost) anyone, since they know that you are incapable of deceiving them. People will trust you and treat you special, in a very nice way.
Best of all, you'll have a spouse that trusts you; children that will be proud of you; business partners that will go great lengths for you; and everyone will be willing to recommend you.