A form of relaxation anxiety which manifests when things are going too well.

This can be caused my low self-esteem and the feeling that the happiness is not deserved and may go away.

Equally this can be caused by high self-esteem and the feeling that the happiness is either too cloying or distracts from the the great artistic endeavour of understanding the soul of the universe.

In either case can probably lead on to self-sabotaging behaviours.