The Lord our God has never failed us and will not fail us. In all his promises he comes through no matter what the situation may be and it is for this reason why we must be confident in the Lord. Because no matter how long it takes, his word will always come to pass.
There are so many instances in the Bible that we can draw inspiration from, take the life of the Israelites, when the Lord promised them the Land of Honey and great things, they had to go through lots of trials and tribulations, temptation but eventually they got there, why because the kept on going even when the going got tough, the sin on countless occasion but always found their way back to the Lord and for that he lead them through the wilderness safely until they reached the Land of their destination. Then one can also draw inspiration from the life of Joseph whose life destiny caused him to be sold into slavery, but in the end the word of God on his life still came to pass and through him a great nation was saved.
Brethren, been hopeful and optimistic in the Lord in the Lord does not mean that difficult times will not come or that when it comes do not do anything about it, rather it should just served as a motivation for you to stand your grounds and hold until till the very end knowing that the Lord will surely deliver on his promise and that he has never failed and will not fail you.