I've actually heard a fairly common motivation tip is to not tell people when you've started a new project or healthy habit.
Some people believe that sharing the news with people is what ultimately gives you the feelgood chemicals, and then suddenly you have less desire to do the thing.
I don't think this is to say that you shouldn't share your accomplishments. In fact, if you struggle with perfectionism, you might never think that you're totally finished a project. But if you're in the tenuous first stages of a new activity, it might benefit you to wait until things are a little more concrete before sharing the fun stuff.