And I will ask what I always ask. Why is it wrong for Jack the Ripper to rip in a universe with no innate meaning. Therefore, define "disgusting". Jack loves a juicy uterus on display, meanwhile I don't. what can we say? Not much!
Well we can say it is wrong, socially destructive and worthy of punishment.
Once we remove the extraneous waffle your argument boils down to the following:
IF there is no God THEN morality becomes weak and meaningless. You find this idea abhorrant. Therefore God must exist.
Your assertion regarding morality in the absence of God is debatable. But whether your assertion is accurate or not your dislike of the assumed outcome is irrelevant with regard to the veracity of God's actual existence.