I agree with you on this. If someone was gonna be hurt if  you didn't show up to thier wedding they should also call and invite you also. If they got thier felling  hurt they need to look in the mirror to see part of the fault. If you are planning something that you fell is important send out your invites early and then follow up. 

My wife and I have also had problems with the Maricopa post office. We live in Tulsa, OK and have a second home in Maricopa in RED. Last year I sent a certified letter from my office in Tulsa to my wife in Maricopa. The certified letter included the insurance verification form for one of the cars we keep at our Maricopa home. My wife never received the certified letter. Ultimately, it was returned to my office by the post office. Shortly after I received the returned envelope I made a trip to Maricopa and delivered the insurance form to my wife.

I called the Maricopa Post Office several times to inquire about why the letter was returned. The Post Master stated that the carrier told her that they did not try to deliver the letter because we did not get that much mail!!

I would suggest that if you are serious about complaining about the Maricopa Post Office that you document your problems and call your Congressman's office.