Wise words. Leave him to his own devices and thoughts. He will make stuff up, anyway, no matter what you do about him. You have shown him your love and friendship. Think of how he will have to answer when others ask how you are, and HE DOESN'T KNOW.
You are right: its his time to prove himself, now, for better or for worse. You have already done your part, and he knows how you feel about the marriage and wanting to try. If he can't step up under these circumstances, is he someone that you would want?
Sorry you are feeling so down, but it also might just be a self-wakeup call.