today i feel drained, ..but the bible tells me to not grow weary in doing good

So I am not sure why we fret about things, because 1)God does not want us to worry about tomorrow 2)We lack putting trust in God and 3)It just really puts a negative attitude in us. But constantly this month, maybe even just this whole year, I have been fretting about my life...where am I headed? will I ever get married? what kind of life am I sappose to live? if I can live the life I was meant to live today, am I? and if this is it, wow life sucks...I just can't see any hope for things getting better, does life get better gradually? or is life just a mess of ups and downs? I think I remember reading a book and the guy talked about ups and downs, ya it might have been that book "blue like jazz", I don't really remember for sure though...but the guy was talking about how he use to think life was a mess of ups and downs, and you lived the downs for the ups, but then as he grew in faith he started to realize that it was not a life of ups and downs, it was a life of gradual maturity in Christ, gradual increase of enjoyingment in life the more we know about God, and along the way these "ups and downs" get us up a valley...though the downs don't really seem to get us anywhere except down, but in reality it is in the downs that we mature in Christ the most, it is where we draw close to Him more and experience life to it's fullest because we are being put in a place where we have a reality check of who is most holy and what this life is meant to live for: for Him, His glory and His alone. But today has been hard for me because I want to just be negative, I do not want to go to work..but God I pray that you would give me a focused mind on You today and would help me to grow closer to you in this day that you have graced me with, in this day that is part of a story line of my relationship with you that will never end, and all I have to look forward to is UP even when the downs point down in my mind..I can learn something in the midst of suffering and the drudgery of the week, I can learn to be constant in my life, I can learn to be constant in patience, in love, in enduring, in being a hard worker, and focusing on the Lord Jesus Christ for the joy that comes through all of this..through ultimately being a servant. The most humbling is being a servant, and every time I surrender I am filled with joy, so even though the choice is hard and the suffering is hard I will surrender and be humble for God today, because I know ultimately that is the best and most fulfilling way to live.