What do you call a person who is utterly independent and a loner?

I was just in the midst of writing a description for a story I am writing, and I'm trying to describe one of the characters, or more rather think of a word I could use to describe them.

They are independent, they do everything by themselves, they enjoy solitude, and believe that friends or socialization is unnecessary and causes nothing but issues. They are quite egotistical and quite narcissistic because of this, but I'm looking for a word that explains their need to do everything alone.

If this helps, my sentence is as follows, or something along those lines:

Marina is a proud _____, she believes that buddies are for weak people, and she could very well cope on her own.

Solution 1:

You might call her a lone wolf:

a person who avoids the company or assistance of others
_{from vocabulary.com}

The linked site goes on to explain:

If you prefer to do things on your own, including taking care of problems and working on projects, you can call yourself a lone wolf, or a person who prefers being alone.

Solution 2:

At first I was thinking hermit, but settled on Individualist

Google result: in·di·vid·u·al·ist ˌindəˈvij(ə)wələst,ˌindəˈvijələst/ noun

1. a person who is independent and self-reliant. "a rugged individualist driven to succeed" a self-centered or egotistical person. "selfish individualists thinking only of themselves"
   2. an advocate of a social theory favoring freedom of action for individuals over collective or state control. "radical individualists, committed to quality of life"

Solution 3:

A recluse.

From The Collaborative International Dictionary of English v.0.48 [gcide]:

Recluse \Re*cluse"\ (r[-e]*kl[=u]s"), a. [F. reclus, L. reclusus, from recludere, reclusum, to unclose, open, in LL., to shut up. See {Close}.] Shut up, sequestered; retired from the world or from public notice; solitary; living apart; as, a recluse monk or hermit; a recluse life [1913 Webster]

Solution 4:

Maverick -- Dictionary.com

noun 2. a lone dissenter, as an intellectual, an artist, or a politician, who takes an independent stand apart from his or her associates.

adj. 4. unorthodox, unconventional, nonconformist