First, I want to congratulate you on your wisdom in turning to forgiveness as soon as you did. Please keep in mind that a period of confusion and anger is normal and so please do not be dismayed when these feelings come to you. Forgiveness is a process and it can take time.
You say you read the Bible and so I am presuming that you are a Christian. If so, then you can read in Genesis 1 that we are all made in the image and likeness of God. This includes both you and your wife. I would urge you to reflect on that whenever you are feeling deep pain: Both of us are sinners and we are both made in the image and likeness of God.
Building trust is not the same as forgiving. Your wife now needs to show, within reason, that she truly is over the affair. Try to see small steps in her that are leading to remorse and a willingness to turn her life around and to turn to your marriage. In time, as forgiveness helps you to be open to trust, your trust will start to grow. For now, please remember: You are both made in the image and likeness of God. You are both sinners. Jesus’ redemption is for both of you.