Update: Turns out I do not have a fissure (or any visible problems at all in my rectum or sigmoid) after undergoing the exam under anesethesia yesterday. I apparently have levator ani syndrome or pelvic floor disorder according to my CRS, which is apparently difficult to treat. So, it's back to the drawing board for me and I am still in pain. : (
Thank you everyone for the well wishes and great advice. Everyone on this board has helped me so much through these years and I am incredibly grateful. I explain more in my diary in the diary section.