I'm not sure of the relatives, but it affects the close ones for real. I personally experienced it. Being into gambling I've suffered much and now I've come out partially. At times the loss can't be accepted and our minds won't work as we think. This affects the family and the close ones. They can see the difference and the same makes them down. Atleast to keep our surroundings happy we should have healthy gambling habit with limits.
Usually nothing you do in your life has influence on distant relatives. I have cousins that live in different countries. Sometimes we see each other once a year, sometimes every 2 years... If I died the only way it would affect them is that they'd have to come for the funeral.