Theists: How can predetermined fate and free will coexist?

[Tonus]

So, God's actions did in a way (weakly actualizing) 'seal that man's fate as the person to betray God'. That in no way took away Judas' ability to choose otherwise. Jesus' message obviously did not resonate with him and the greed in his heart was obviously there. He went to hell not for his weakly-actualized-by-God actions, but for the same reason anyone else will--rejecting God in his heart.

But God's action put Judas in the position of taking the action that betrayed Jesus. Absent that, what would Judas' life have been like? Would he still have earned a ticket to hell? Was he always going to be wicked regardless of God's actions and it was simply a matter of using someone who was screwed anyway? Surely we've heard or read of people who made changes in their lives and became completely different because of some experience. Was Judas immune to this or did God realize that --absent any divine interference-- he was already hell-bound? This speaks to a God who had a chance to save Judas and instead used him as a convenient prop.

The notion that my life might be laid out along a path that I cannot change but that I cannot see means that my life would still have the appearance of being under my control. In which case, there's nothing to worry about. But it's troubling to think that my path was laid out long before I was born and I have no way of avoiding the decisions that would lead me to eternal joy or eternal horror. That doesn't keep you up at night? The possibility that your fate is to turn on God someday and be condemned to eternal hell without any recourse because it's how your life's thread was directed? Or do you feel that you will be granted heaven because... ?