I and many Christians often get into a negative place sometimes. We have zero reason to be negative, but it's very easy to slip into the negativity. It's like black ice. You don't even see that it's there until it is too late, and you're spinning without visible hope of stopping. Except you eventually stop spinning on black ice, because an object in motion will remain in motion until acted upon by an equal and opposite force. Physically that principle is pretty simple, but how do we mentally do that?
Some people are naturally positive, they refuse to think otherwise. For those of us who are less inclined, it requires a lot of dedication and practice. Refuse to think of things as ending, but rather think of things as a new beginning. I'm not saying that I'm a new and instantaneously reformed positive thinker, but I am trying. David says in Psalms 6:2, "Be gracious to me, O LORD for I am languishing; heal me, O LORD, for my bones are troubled." I know that it is a struggle for me to remain positive in all circumstances (See 1Thessalonians 5:16-18), but I also know that while being a Christian doesn't mean bad times will never come, I will be alright (See Isaiah 43:2).
Part of why I wind up in a negative place all the time, is that I rely on other things to make me happy. For example, I often rely on my job, my friends, my family, etc. to make me happy. This weekend, I attended a women's conference, and a woman said something in her testimony that really spoke to me: "When you put your trust and attention on anything other than God, you will be let down." That is so true. Some days I let how good my day at work was dictate whether the day was a good day. Other days I let it be how much time I got to spend with friends dictate how good my day was. None of those things can every bring lasting happiness.
If something disappointing happens in our lives, it is natural to go to God for help. That's ok, God wants to help us! However, it is important to remember that while it's ok to do what you can to fix the situation, sometimes it's just not in His design for it to be fixed. That's ok. God's been planning things for over 2000 years. Psalm 139 talks about how God has carefully put together each and every one of us. He's a craftsman who by hand pieces us together each individually. We're not stuck in a mold, and created en masse. He's obviously a better planner than you or I will ever be. I don't believe in predestination, but I have the choice to allow God to show me my greater purpose. I choose what trials I allow to defeat me, and I choose which battles to fight. However, God is with me either way I choose.
So I thank God for the new opportunities he puts in my life. Even that bad experiences help me learn and grow, and they draw me closer to him. I must remember to be thankful for all the good things that still exist when I am facing trials, because they come from him as well. I must learn not to blame God for my situation, but rather ask God what I'm supposed to do to change it. I must learn to not beat myself up if negative thoughts enter my mind or cross my lips, but rather ask God for healing to prevent me from doing it again.