Cherophobia

Cherophobia is the irrational fear of happiness. It came from the word “cheros” which means “to rejoice” and “phobos” which means “fear”. A person with cherophobia is aversive to social functions which are generally characterized as “fun”, and opportunities which may lead to happy feelings. The cause is usually attributed to illogical thinking such as "feeling happy will be followed by a negative emotional state", "being joyous makes one bad", "it is in vain to strive for happiness", and "it is bad to let others notice one’s happy state".