"the basic right to be treated as a human being is fundamental to any civilised society"

Nobody could disagree with that Jim, but you go on to equate discrimination on grounds of skin colour or race, with discrimination on grounds of sexual behaviour.
There are many issues involving "discrimination" against various types of sexual practice which I am sure even you would agree with.
Complicated issue which require to be dealt with in an adult fashion, with all the facts, including associated health issues and effect on children taken into the equation.
As you already stated the latest "marriage" legislation was pushed through by media pressure with almost no political debate.

There is a new thread on Mudcat dealing with pressure to legalise Polygamy....would this come under your criteria for ""the basic right to be treated as a human being is fundamental to any civilised society"?