Ok, not quite sure what your wife's current status is - you said that she's due to have her rectum removed because of a stricture - but you also mentioned a stoma - so am I guessing correctly that she has what was supposed to be a temporary colostomy - but now is slated to have the rectum removed, thus having a permanent colostomy?
If so, I had a similar situation - I was supposed to be reconnected but developed a stricture just above the rectal stump. While they could dilate, I was left no choice but to have a permanent ostomy.
Having your rectum removed isn't too difficult an operation, but in my 10+ years of being on various support forums, the recovery can be very easy (like it was for me) or unfortunately, it's possible to have minor complications - like getting an infection where they sew you closed, thus greatly extending the healing process. Some have shared that they ended up getting excessive amounts of scar tissue from the procedure, and that can lead to some discomfort when sitting for long periods of time. Another small odd side effect is the urge to go to the bathroom normally. They call it "phantom pains." There's no medical explanation for it, but strangely, it happens to some - happened to me recently, and it's been 7 years since I had mine removed.