Yes, you can change, with God's help—and I want to assure you that God wants you to change. Although your background has made you suspicious of people, God doesn't want you to carry this burden the rest of your life.
The most important thing I can tell you is this: God loves you, and you are of great value to Him. He knows all about you and your background; He even knows you better than you know yourself. And yet He still loves you! He loves you so much that His only Son, Jesus Christ, was willing to come down from heaven and die on the cross for you. The Bible says, "This is love: not that we loved God, but that He loved us and sent His Son as an atoning sacrifice for our sins" (1 John 4:10). More than that, God wants you to be with Him forever in heaven.
By a simple act of faith reach out and receive the gift God offers you right now—the gift of Jesus Christ and His salvation. Then realize that you are now His child forever, and nothing can separate you from His love. When doubts come, ask God to remind you of His constant love for you.
Then ask God to help you reach out in love to others, just as He has reached out to you. All around are people who wonder if anyone really cares for them, and God wants to use you to touch their lives for Christ.