i think this applies both to people, as well as to thoughts & feelings we experience.
i think the best way to part with disturbing thoughts & feelings is with non-attachment, non-aversion; ... just observe & let go.
As for people, i try to be open and accept anyone who invites; ... but if they abuse, i part ways.
Positive company does not have to be Buddhists-only, i think - i had very positive experiences with a witch, with Martial Artists, with Digital Artists, with Warsaw University's Scientists, as well as with parts of the Catholic Church, for example.
i do try to respect our energy & time, i do not wish to squander these with wrong people.
FIVE WISDOM BUDDHAS
OM MANI PEME HUNG
Namaste, blessed be.