I am trying to be a very individualistic person from now onward. Previously, I used to fear what other people would think of me when I disappoint them by saying no. But now I've realized that saying no is an art and we should embrace it by applying it at the right time, in the right situation with the right person to prioritize own's interests.
I know it's hard to embrace this habit completely but since I am moving on a path to becoming a more complete human being, I should apply it to live a complete life and work on my own interests rather than working for others' interests.