Pain above the rectum!

Hello there,

I have been having severe pain above my rectum for about 3 months now. It starts hurting when I have been sitting for about 5 minutes and then it starts hurting more and more. When I push with my fingers on the bone area above my rectum I can feel the pain. I haven't seen a doctor yet and I am 41 years old. I can't do the correct spelling of the word, but I have been told that it could be my cosic or custic bone where I am feeling the pain. Can you please give me advice as to what this could be. The weird thing about this is that my fiancee has the same problem, he started with the pain first and now I have it. Please help!