If you had been the only person alive through Adam, He would have had to do it for your sin. Same as me. We necessitated His execution, so we are directly involved.
This is only marginally true, in that, if there had only been one person, it would have been necessary. And that's the way I looked at it until something completely revelatory - and obvious - crossed my mind.
He didn't have to go. No one forced him to. He made it abundantly clear in the garden that he wasn't crazy about the idea.
When he was about to be betrayed, he could have left. Or just left early. He didn't even have to be there at all, since he knew who was going to betray him - and how.
When he was under trial - he could have said something. When he was on the cross - he could have left. Anytime.
No one MADE him do it. He CHOSE to. He *chose* the cross for your sake. So the better way to see it is - if you had been the only person alive through Adam - he still would gave gone there. By choice. He loves you that much.
It's an important distinction. The previous way was how a church I attended taught - that it's all your damned fault thou vile sinner. So feel guilty, you jerk - you put him there.
But the real way is - that's how much he loves you. He stepped up to the gallows and told the hangman - I'm taking the fall for him. Hang me instead. Nope, no one put me up to it. This is my friend.
So your attitude for such grace is gratitude and not guilt. When someone saves your life, you're grateful.