Keg, I too would dearly love to know how it will affect society. Same-sex couples already exist, they already have children, they already adopt children, they won't be getting married in your church if your church doesn't want it, our opposite-sex partners will still be there in the morning, men and women won't suddenly develop a hankering for a same-sex marriage rather than an opposite-sex one.
The nexus between marriage and religion is well and truly broken - that horse has well and truly bolted given the fact that 75% of us get married with civil rather than religious celebrants. That was in 2015 and the trend was not towards using religious celebrants.
As much as you might want to cling to traditional values, society has moved on.