How can I get visitation right of my children?

I have been married for 17 to 18 years and we have a 16-year-old child. Last year, my wife left to stay with her parents and has not returned since. The reasons for her departure are not clear. Sometimes she claims that I drink and do not have my own income, as I work in my father's shop. At other times, she cites my father's attitude as a reason for not wanting to return, or she asks for more time to think. This situation has persisted for the past 1.5 years, during which her family has made significant efforts to prevent any contact between us. It has become extremely difficult for me to meet with my child.