Neglecting to mention that Gilgamesh didn't want to kill Humbaba, but Enkidu talked him into it. (Enkidu is the patron of poor decision making.) And after Dumuzi, I wouldn't marry Inanna either: http://etcsl.orinst.ox.ac.uk/cgi-bin/etcsl.cgi?text=t.1.4.1#

Then there's the whole thing about Gilgamesh sending Enkidu into the afterworld after his lost toy or game.