1. You are correct about the unseen mold and how much it has spread. If you get far enough in the loaf to where you can’t taste it yet, you could eat it with no harm, but I would toss it personally. 2. I do not think you are obligated to drop the friendship. It would have been nice if your friend had been more open with your roommate (Called, said I had a good time, but I don’t think dating will work between us, can we be friends?) If it was me that might affect my feelings for my friend. To salvage what you can, tell the rooommate in no uncertain terms that you read the friend the riot act and you did not approve. Possibly even apologize for setting them up. Try to meet the friend away from your home. If unavoidable, give the roommate a heads up.