Adverse life experiences such as physical/emotional abuse may make some turn to alcohol and drug abuse (and smoking). These are just coping devices and without them they may suffer with unrelieved stress which can lead to other health problems.
There’s more to it than just a bad habit they picked up.
You know quite well a large percentage of people do not become addicts for escapism from abuse.
You know quite well a large percentage of people do not become addicts for escapism from abuse.
Further not everyone abused turns to drugs.
You cannot use it as an excuse for these people. Its may be a factor but there are many factors,none of them absolve them of responsibility.