According to verse 10, God was grieved in His heart and so He said that they would not enter into His rest. Many that were in the desert did not cross over into the promised land. Don't let a heart of unbelief be in you. Don't you depart from God because of unbelief. If you feel like the battle is getting to be too much for you, talk to God about what you are going through and allow Him to minister His love to you. You could also get some of your brothers and sisters to bear you up in prayer and together you will hold unto the confidence you have in God.
The Israelites couldn't enter because of their unbelief. Don't let Satan put unbelief in your heart. No matter what you are going through or what you may have to face, God will always see you through, if you trust Him. Allow Him to prove Himself to you, and when He does, don't doubt Him again. God is a God who cares and understands and is able to meet your every need.