I don't think either of us could live with ourselves

"I don't think either of us could live with ourselves."

If you and I decided to rob the 7-11, but accidentally shot and killed a clerk, I don't think we could live with ourselves.

If you, Bob, and I went swimming, challenged Bob to belly-float over the waterfall and he died trying, I don't think we could live with ourselves.

We would hate ourselves and live with regret and guilt, always wishing we could relive that time and do it differently.