Even the egocentric and bubbly among us can be sensitive and touchy. Personal failings as well as monetary and relationship problems lie heavily on us, affecting our mood-swings and the quality and energy we put into our creative and other life. In some cases, including mine, the result is spots of anger, irrational exuberance, minor paranoia. I think it's partly to do with our aloneness.
Creativity comes with a load of private responsibility.
Two or three failures in a row, in lifemanship or in our art, can depress and cause a setback. It's always seemed to me that a main part of our job is maintaining some sort of self-delusory defense. An admirable quality I often note in artists is the intelligent way they are able to deal with the ups and downs. It's good to have someone to whom you can confess and share the deepest and most intimate feelings of concern. One needs a like-minded fellow traveler for this.