A lot of the guys I met in the YPG had seen way more combat than that and still yearned for it. One of them was retired foreign legion that did this as his retirement. When we were getting shot at one of the older guys would get viscerally excited and joyful, and he had seen many dead.
Junky is a good description of what they were. They wanted another taste. I can't imagine after 5+ years of that life how you would detox from that, not easily I imagine.