Veterans and SUD
Studies show PTSD and substance use problems are strongly related in people who served in the military and in civilians. Some people try to cope with PTSD symptoms by drinking heavily, using drugs, or smoking too much. People who have problems with drugs or alcohol are also more likely to develop PTSD. The good news is that treatment works, and therapy can target both problems at the same time.
Sources:
https://www.ptsd.va.gov/understand/related/substance_abuse_vet.asp
https://www.ptsd.va.gov/publications/print/sudptsdflyer.pdf
https://www.addictioncenter.com/addiction/veterans/
https://www.samhsa.gov/data/sites/default/files/report_1969/Spotlight-1969.html