You walk away by stepping out on the faith that GOD has better blessings for you ahead. When God's grace and blessings have been lifted from a situation, you no longer want to stay there. IF you no longer feel the joy, enthusiams, or happiness that you once felt, then I believe that GOD's grace has been lifted and its time to move on. Grace opens doors for us. Grace makes the way easy. Its like this, have you ever had a situation just seemed to work itself out, things falling easily into place with little or no effort from you? Well, that's GRACE.
However (of course that was coming) if you no longer feel the joy, enthusiam, or happiness that you once felt because of something that you done (i.e. breaking one of the 10 commandments, etc.) then that has nothing to do with it. God is not going to use a sin or break one of his convents with us. For example, let's say a single woman falls in love (both physically and mentally) with a married man that she has been seeing. This single woman tells herself that this married man was sent to her by GOD and that they were meant to be. WHAT!!

GOD is not going to "break up" a marriage (one of his convents AND commandments) in order to send her a man by having him to committ adultery. Now if the man was already divorced when he met her, then that's a different story
Anyway, everything really boils down to prayer. In the book of James, he tells us the " if you want to know something, just ask! GOD delights in us asking Him. But when we ask, we must do so with a faithful and expectant heart that he will answer us, because a heart full of doubt and unsureness will twist and turn with every bump in the road".
Ok, let me shut up because I've started preaching now.