You say "I thanked Him, but nothing changed." The circumstances often don't change, nor does how you feel about what is going on. But something else happens: you begin to see through the eyes of faith that God really does love you, and you have the secure hope that all things do work together for good. And the peace! Not to mention the joy from knowing that you have obeyed God. He really does bless efforts of obedience with a real sense of peace and joy deep down in your heart. Then, amazingly, you realize that you do feel thankful for this crazy, unpleasant circumstance! It's like a ball that you get rolling, and then you can't stop it. It really does lift you up above the winds of the trial, and you are spiritually stable even while the boat is rocking.
Do you force yourself to be thankful for something hard? It's not hypocrisy- it's obedience, and when practiced, there are many blessings to follow!!