I Have Had Colitis Since I Was 8 Or 9

I have had colitis since I was 8 or 9 and an ulcer in my 30's and still have the ulcer. I believe I may have ibs or crohns because I have had muddy to watery diarrhea and went to the hospital quite dehydrated and a 12 pound weight loss. no blood, stool cultures were all negative and h-pyloric test today was negative. would cancer be a first choice or one of the other two above be more realistic? I have a colonoscopy scheduled for the 17th of this month, however my husband is in hospice care in our home organ ca bone ca and alzheimers .
just a little scared and will not go thru the torture my husband has gone thru for the last 18 months.