Should I be offended?

I received this email today:

Subject: FW: Please Read: Today is your day!

Today is the international day for the mentally
disabled. Please send an encouraging message
to a mentally retarded friend--as I have just
done for you. Just thought I'd let your retarded
ass know I don't mind being friends with you. I
don't care if you lick windows or even if you
wear a football helmet to work. It doesn't bother
me that you wear your underwear on the outside
of your pants. All I ask is that when we go to the
club, you drive so we can park up front. You hang on
in there because you are doing great! You are special,
so keep trying! Have a great day!
--Your friend Always

Jim