It is interesting that the ED was after the take down. You have implied that your pouch does not function well. Have you had a scope since take down to see what it looks like? Is your general energy level good? A poorly functioning pouch can really sap ones energy. I find that my sexual function is directly related to my overall energy level
Did the wife give any rational for her decision? That is a pretty big club, so to speak, to swing at you out of the blue with no reason. Believe me there is a reason, and she needs to level with you.
Just for the hell of it you should try the Viagra type drugs, see if they work. Why? because my guess is your marriage is on shaky grounds. Often you can split the pills sometimes even a quarter of a pill will work. This greatly lessens the cost.