Because He didn't chose to "befriend" us, He chose what to do with us because He knew we are His friends. That's what predestination is. It's very simple, From God's omniscience He saw who would believe and who would not. He then separated the believers from the unbelievers (in His mind). Now, (looking at the believers only group) from his knowing us (My friends) beforehand (foreknowledge), He chose when and where to place us. You and I got placed in Christ, King David got placed in Israel, Adam the Garden, Noah the Ark etc. etc. Each placement has a particular purpose for God's plan to be worked out according to His will.
The problem with you premise is that us "befriending" God is totally backwards, since friendship with Him is not in our DNA. The natural disposition of the human heart is
enmity with God! What do you think the doctrine of Reconciliation is all about? If God predestined any of us to salvation based upon our friendly attitude or disposition towards him, then why would he need reconcile anyone to himself. Why would he need to reconcile friends to himself?
You have no biblical understanding of predestination. Predestination is not contingent on man's will, man's attitude toward God or anything that man does. Salvation has nothing to do with man's efforts to please God. Have you never read?
Rom 9:16-18
16 It does not, therefore, depend on man's desire or effort, but on God's mercy. 17 For the Scripture says to Pharaoh: "I raised you up for this very purpose, that I might display my power in you and that my name might be proclaimed in all the earth." 18 Therefore God has mercy on whom he wants to have mercy, and he hardens whom he wants to harden.
NIV
Moreover, in your understanding of predestination, his grace would actually be a reward to his "friends", would it not? He would be rewarding us for our friendship toward him.
Ah yes, the potter's wheel. Guessing you have never done pottery.
Is this where I'm supposed to chuckle or something?
That is your assumption (what I bolded). The problem is you assume this passage means a division between receiving mercy and being given no mercy whatsoever. God is merciful. Everyone receives mercy and grace, because this is who God is. It's a matter of how much or how little one receives. When speaking with Moses, it was a matter of Moses being given an extra dose of mercy and grace. (Ex.33:19) Paul is not saying there are those who receive mercy and there are those who receive no mercy. He is saying, under the pressure of the potter's wheel, the clay responds to His touch. Some clay resists and some clay yields. It's the nature of the clay and God will do with it as He sees fit.
The subject of Romans 9 is election. It is talking about eternal salvation. And Romans 9 itself divides the world into two groups: The elect and non-elect.
But having said that, there aren't two different kinds of clay. There isn't yielding clay and resisting clay. There is only one kind of clay -- the clay under the universal indictment of Paul in Romans 3! Not only that but you totally miss what v. 21 is teaching. There is only ONE lump of clay. Here's the verse with some added context.
Rom 9:19-21
19 One of you will say to me: "Then why does God still blame us? For who resists his will?" 20 But who are you, O man, to talk back to God? "Shall what is formed say to him who formed it, 'Why did you make me like this?'" 21 Does not the potter have the right to make out of the same lump of clay some pottery for noble purposes and some for common use?
NIV
According to you, the Potter is a very poor craftsman, isn't he? He can make some pots very well ("for noble purposes") and others not very well at all ("for common use") -- both from the same lump of clay!. And notice that it is the Potter making the clay! The clay has no say! It is God who patiently bore the objects his wrath prepared for destruction, and who chose to reveal his glory to the object of his mercy whom he prepared in advance for his glory
No-one believes against their will.
Congratulations! You have finally said something upon which we both can agree! Since all sinners come into this world spiritually stillborn (as in DEAD), then man's will is truly a non sequitur in this discussion. After all, the essence of your objection to the Reformed understanding of predestination is that God does not overpower any free moral agent's power of choice. And I agree totally with you on this point -- but not for the reason you think, sir. I agree because we mere mortals do not possess the will power to raise ourselves from the dead -- from our own spiritual tombs. Only God has that power! Therefore, how in the world can God force anything on anyone, when none of us have the [will] power to do only what he can!? When Jesus raised Lazarus from his physical tomb, do you really believe that Jesus forced his will upon Lazarus --that he made Lazarus do something against his will that he couldn't do in the first place!?