IRS why do you hate me? (Edit included)

Oh.. my.. god.. I feel the need to rant at the moment.

I have had my business since October 2006 and still happily running it though I am still not all that known nor do I make a whole lot. I have been paying both State and Federal taxes this entire time and never had any problems with either until last year where the IRS sent me a letter back requesting that I PROVE that I am self employed even though I did have it clearly stated on my paperwork that I was. Wrote them a response, sent it in and without any problem I was able to get what little money I was owed. This year has been a different story. Even with sending in a certified copy of my business license  with my tax form, I STILL got the same letter as last year. Wrote yet another letter explaining that yes I am self employed and that this had happened the previous year as well. Thought that everything was fixed and understood but couldn't understand why I hadn't received the money that was due. Well I just received my answer.. in the form of yet another letter. Scrolling through the red tape figuring it was going to be exactly the same as before, I come across the following paragraph:

The income you reported on line 21, Form 1040 EZ indicates you may be liable for self-employment tax. This tax applies when the earnings do not reflect the withholding amounts for social security and medicare taxes. For example, if you receive cash for services performed or Form 1099-MISC for nonemployee compensation and the payer did not withhold social security and medicare taxes from your income, your earnings may be subject to self-employment tax. Please complete Schedule SE, Self-Employment Tax, to determine the tax amount. 

As I read this out loud to my boyfriend who spent a good 10 minutes raging saying it was completely unfair to me since I did send all of my information clearly stating that I was self employed, I found myself laughing my head off at the complete stupidity of it all. Looks like I get to play this silly little game with IRS some more even though I don't make enough to even be on any form of medicare, this is a single person business, and the fact that if they wanted to pull the self employment tax card, they should have done it sooner and not nearly 6 years down the road. Ugh now I get to try to find this form they're wanting me to fill out along with a letter and send it in. All of this for $125. Really people? You're giving me this much trouble just because you owe me money? REALLY? God I'm going to need a lot of coffee and good company after getting that thing in the mail.

EDIT: It would appear that, after talking to my folks about this little letter I received, that there is a scam going on right now where people send out official looking letters as if by the IRS that requests you to pay on various taxes. I had a feeling that something might be up but I can't call the OFFICIAL IRS number provided by irs.gov until Monday to double check on this. Guess updates will come next week then.