You say you are going through peri-menopause, are you taking anything to treat the other symptoms of that? I recently started taking the birth control pill again just to help with the period issues and hormone fluctuations. I was having a BIG problem with irritability and I think that has gotten a lot better since I started the medication. (I do find myself being rather short with my 11 year old lately, he seems to feel that he needs to make noise ALL THE TIME, fart noises, clicky noises with his tongue (that are really loud), anything. I try to take a deep breath and ask myself, is he really all that annoying or is it just me???)
My doc told my that if the pill didn't take care of the irritability we could add some Prozac, but after 3 months I really don't feel like I need that additional medication.
I don't know how old your kiddos are but you might try giving them a time frame like "Please go play without Mommy until the Barney CD is over, or the Dora episode is over." Anything to give yourself just a few minutes of peace to take deep breaths and relax.
Good Luck.
M