Abbreviation Meaning

B-Pics  Boudoir Pics commonly given to FI as a gift
BC,BCP Birth Control, Birth Control Pills
BF Boyfriend or Best Friend
BM Bridesmaid or Best Man
BP Bridal Party
BTW By The Way
C&P Copy and Paste
DD Dirty Delete
DF Dear Fiance
DH Darling Husband
DW Destination Wedding
E-ring Engagement Ring
E-party Engagement Party
FG Flower Girl
FI Fiance
FIL Father-In-Law
FILs Future In-Laws
FBIL Future Brother-In-Law
FFIL Future Father-In-Law
FMIL Future Mother-In-Law
FSIL Future Sister-In-Law
F/U Follow Up
FWIW For What It's Worth
GBCK  Goodbye Cruel Knot
GF Girlfriend
GM Groomsmen
GTG Knottie Get Together
HM Honeymoon
HTH Hope This Helps
IHO In Honor Of
ILs In-Laws
IMHO In My Humble Opinion
IMNSHO In My Not So Humble Opinion
IRL - In Real Life
JK Just Kidding/Joking
JP Justice of the Peace
KTFU Knocked the Eff Up
LOL Laughing Out Loud
LTBM Living Together Before Marriage
MIL Mother-In-Law
MOH Maid/Matron of Honor
MUD Made-Up Drama
NFT No Further Text
NH New Husband
NWR Not Wedding Related
OMG Oh My God!
OOT Out of Town
P&E Planning and Etiquette Board
PIB Picture In Bio
PIP Picture In Post
PSA Public Service Announcement
RB Ring Bearer
RD Rehearsal Dinner
RP Repost
ROTFL Rolling On The Floor Laughing
SAHM Stay-At-Home Mom
SAHW Stay-At-Home Wife
SAHD Stay-At-Home Dad
S/O  Speaking Of
STDs Save-The-Date Cards
TIA Thanks In Advance
TMI Too Much Information
TY Thank You
WP Wedding Party
WR Wedding Related
XP  Cross Posted

Specific Pgh lingo:
AW  Attention Wh_re (Jokingly)
FIF Freaky Internet Friend
JealousE  Jealous with an E. Long story from an old, crazy knottie, but it basically means that you are really jealous of something.
OMGWTFBBQ!  Oh My God What the F, BBQ!  Basically used when you can't believe or are excited about something.
PW Post Wh_re  (Jokingly)
TWSS That's What She Said (Not Pgh knottie specific, but awesome)