Here's a list of words that you can substitute for "friend." Some of them are synonyms, some are words that suggest a particular kind of relationship.
Print versions: Word file, Acrobat file
Words for "Friend"
accomplice
acolyte
acquaintance
adherent
admirer
advocate
aficionado
ally
alter ego
amigo
angel
angels
apologist
apostle
assistant
associate
attendant
babe
backer
beau
believer
beloved
benefactor
best
betrothed
bird
blade
boon companion
bosom buddy
boyfriend
brother
buck
bud
buddy
buff
bunkie
cavalier
champion
changes
chap
chaperon
chum
cohort
collaborator
colleague
 colleen
companion
compadre
comrade confederate
confidant
consort
copartner
counsel
counselor
co-worker crony
crush
dandy
darling
date
dawg
dear
dearest
defender
devotee
disciple
distant friend
dude
employee
encourager
enthusiast
escort
fan
fanatic
favorite
fellow
fellow member
fiancé
fiancée
flame
flirt
follower
friend
friends
friendship
gent
gentleman caller
gentleman friend
girl
girl friend
girlfriend
 gorgeous
groupie
guide
guy
heartbeat
heartbreak
helper helpmate
henchman
honey
intimate
kitty
ladies' man
lady friend
ladylove
lass
lassie
love
loved one
lover
lover boy
man mate
minion
miss
mistress   
old lady
old man
pal
pard
pardner
partisan
partner
patron
pigeon 
playmate
pleader
promoter
proponent
retainer
Romeo
shipmate
sidekick
significant other
significant someone
sis
soul mate
 spark
spokesman for
steady
suitor
supporter
sweetheart
sweetie
sweetie pie
swell
true love truelove
upholder
valentine
well-wisher
woman
wooer
young blood
young lady
young man