James T. Webb, Ph.D, author of A Parent's Guide to Gifted Kids has a newly released book (2013, Great Potential Press) which may be of interest and provide expert guidance and support: Searching for Meaning: Idealism, Bright Minds, Disillusionment, and Hope. There is a free online book preview sample at this link.

The table of contents and subjects covered can be previewed on Amazon, using the "look inside" feature.

Some topics include idealism as a characteristic of the gifted, the relationship between anger and depression, examining one's life, managing one's emotional state, turning disillusionment into opportunities for personal growth, unhealthy coping styles, healthy coping styles.

Existential depression and other forms of depression are discussed. The book ends on a strong positive note in discussing happiness and lasting contentment.