Since always humans have been trying to find freedom whether it has to do with where we come from, our skin color, sex, or for just being who we are. Gay marriage has been a big issue for the past years, because for them not being able to be married was stopping their right of freedom.
https://www.dissentmagazine.org/article/a-right-to-marry-same-sex-marriage-and-constitutional-law
This article talks about how for years all across our country people have been trying to have the right to marry someone with the same sex. Marriage is something that anyone can do whether you're religious or not, marrying is and it has become something that everyone waits for in their future. To create a family with someone that you care about and love. Some people over years haven't be able to do that legally and there for they believe that's taking away freedom from them.