Have you ever sought out someone you wronged to apologize?

What would you do if you found out your boyfriend withheld the truth from you concerning some important matters at the beginning and throughout the relationship out of fear of losing you?
How do I balance this? I want to be an honest person who stands by their word. But I also think that the people I interact with use circumstances to get me to make deals that favor them. How uneven does a deal have to be to be invalid?