"Though they were not yet born and had done nothing either good or bad—in order that God's purpose of election might continue, not because of works but because of him who calls— she was told, “The older will serve the younger.” As it is written, “Jacob I loved, but Esau I hated.” What shall we say then? Is there injustice on God's part? By no means! For he says to Moses, “I will have mercy on whom I have mercy, and I will have compassion on whom I have compassion.” So then it depends not on human will or exertion, but on God, who has mercy. For the Scripture says to Pharaoh, “For this very purpose I have raised you up, that I might show my power in you, and that my name might be proclaimed in all the earth.” So then he has mercy on whomever he wills, and he hardens whomever he wills."
I bolded a few points for the sake of clarity. These are emphases meant to be understood in Paul's letter to the Romans. He's teaching the doctrine of election; God's free right and decision to choose those He will save and those He will not. The question is not how can a person accept and believe this, but how can you not after seeing the clearest of scriptures on the subject here? Forget your angry thoughts of puppets and robots for a second and reread the previous scripture! Could Paul have been more clear for us? It depends NOT on human will, but on God who hardens some and has mercy on others. He even answers your objections in the rest of the chapter. My advice is to read the whole chapter humbly and prayerfully. May the Lord lead you to the glorious truth of His sovereignty and give you a God-centered view of salvation in which man is dead, blind, and in need the Holy Spirit, not the power of his sinful, broken will.