Maybe you are being over sensitive about your friends ignorance of the ills of prostate cancer and prostatectomy. I was fortunate to not have incontinence but dealing with this cancer is ongoing. Sure, I have ED as a result of this but, I deal with it. I have a girlfriend who is understanding and without my suggestion, she is educating herself to my condition. We have wonderful sex because we are very open minded and use the tools available to me for erections. I certainly wouldn't be offended by a friend saying to me in a similar situation that I might get lucky tonight. It's what people do and it isn't offensive to suggest such a thing. I suggest that you may need to get some counseling to deal with your insecurities about your condition. You'll live a much happier life if you just chill about this. You could be enjoying great sex with your wife and maybe even make her happier.