Radical Individualism vs Eremitical Life

[[Dear Sister Laurel, what is the difference between a radical individualist and a hermit according to Catholic teaching?]]

This is a question I have touched on many times in various posts, but not a direct question I have ever received before this. There are several posts which deal with the question  but see especially Why isn't Your Vocation Selfishness Personified?  and Eremitism or Exaggerated Individualism?  The essential answer to your question is found in the canon governing this life. This would constitute "Church teaching" in the sense your question means it. It reads ". . .[this vocation is lived] for the praise of God and the salvation of the world." 

There are many reasons for embracing solitude and all of them may benefit the one doing the embracing. Some of them are mainly or primarily meant for this and others are ONLY embraced for this reason. The vocation of the diocesan hermit (and any hermit living his or her life in the Name of the Church) differs in that it is, by definition, lived for the sake of others, first of all God, then others, and only then oneself. The hermit witnesses to a life lived with God as THE covenant partner; she witnesses to the completion or redemption of a covenantal life lived in and with God and she does so so that God might one day be all in all and others, especially those who might have been isolated by the circumstances of life, may be given hope for the redemption and transformation of these same lives. 

As I have noted before there is a great difference in living in a way which suits one (for instance, because one is a writer, an artist, or even someone gifted in religious experience, as well as for more negative reasons --- failure in relationships, chronic illness, inability to live in a complex contemporary world, etc) and living in a way which suits one BECAUSE it is a way of loving and serving God and others. Hermits embrace a desert vocation for this latter reason; the former reason (it suits her) is never enough to shape one's life or justify calling oneself a hermit in the Church's sense of this term; for that reason the Church does not tend to profess and consecrate people for such inadequate reasons.