I found it a chore that I’d rather not do. It just seemed silly, writing a note and thanking someone when I had already told them thank you in person when I had received the gift!

People complain on social media, the news, etc. all day every day. Memes are created from complaining, people go viral ranting about something petty. We’ve been raised to complain. 

The thoughts you have most--the thoughts that dominate your everyday life and activity--are generally the thoughts that will move you in any given direction. If you tend to think negative thoughts, that bad things will happen, or that you're a terrible person etc., your life will move in that direction. Conversely, the opposite is true.