There is one truth that has always helped me when I have struggled with the difference between God's timing and my timing–and my resulting battles with impatience and resentment. It is found in one of my favorite verses, Psalm 84:11 "For the LORD God is a sun and shield; The LORD gives grace and glory; No good thing does He withhold from those who walk uprightly."
Here is how I use this truth. Do I have the thing I want? If the answer is no, am I walking uprightly? If the answer is yes, the thing I want right now must not be good for me (at least for right now).
I find this a helpful exercise when I am tempted to desire things I don't have. It is my prayer that it will help you as well.
By the way, this is not original with me. I think I learned it from Rick Holland, the College Pastor at Grace Community Church, but I'm not sure who to give credit to.