I hear people of strong faith talk about asking God for insignificant things. Then being pleased that God has answered their prayers. I want to say to them that God has nothing better to do than sort out their trival worries, while so many suffer horrible, horrible problems. The irony seems lost on them.
Breast cancer is a dreadful disease. My mother is fighting it at the moment. I think it's winning. They are making advances but some cases seem totally resistant to treatment and then eventually you run out of options. It sounds like your wife had an aggressive form of the disease. You would have needed to have had a very sharp, forward thinking doctor willing to try every avenue to help her. Even then I've seen women research every possible new treatment available and try every debiliting chemotherapy and still die within a short time.
I am so glad you have found this board. I hope you will find comfort in the association here. My heart goes out to you for the loss of your lovely wife and the loss of belief in something that you thought had all the answers. Be kind to yourself and take things at your own pace.
Hugs Marilyn