A , woman of your age group and single maybe not eating properly. Olive oil should be added to your diet and to every part of your diet, a salad a day will take you to the toilet, and believe me take a expresso coffee in the morning this will help believe me, also and they told you this before and probably you did not follow the advise
fruits, fruits and vegetables are needed, if you hate those, raisins one or two boxes a day the small 40g boxes take you to the toilet, I this doesnt work, let me know I have a lot of advises.
I wonder if they did a colonoscopy to evaluate your colon? The bloody stools could be secondary to Chronns Disease, even when people with C Disease have more diarrhea, also Ca of the colon, and interanal hemorrhoids give that bleeding, also some sexual practices produce those bleeding and constipation. But I think a blood work to evaluate CEA from your colon even when this is not a diagnostic weapon, will help. Do no take no for an answer if a doctor turn you down go to another, and get this done, maybe you are just constipated because you hate to see the blood in the toilet and or you hate to have the BM, something mental not Physicial, do the colonoscopy, Diverticulis could give you constipations in certain cases. Godspeed.