"Reign" implies a period of rule or dominance, usually associated with a monarch. It's not an appropriate word to describe an addiction.
Here are some possible ways to correct the sentence:
* "He was inspired to begin his 35-year addiction?" (This focuses on the start of the addiction)
* "He was inspired to continue his 35-year addiction?" (This focuses on maintaining the addiction)
* "What inspired him to struggle with his 35-year addiction?" (This emphasizes the difficulty of the addiction)
You could also use a different word altogether, depending on the intended meaning:
* "He was driven to his 35-year addiction?"
* "He was compelled to his 35-year addiction?"
The best way to correct the sentence depends on the specific context and the intended meaning.