Do you think same sex relationships are right? What do you think about civil partnerships?
There is a hidden assumption here - that if something isn't right it's wrong. It's perfectly possible for something to be less than the best we'd like and still not wrong. I want to get that out of the way to start with.
I think we'd all agree that the best thing, the thing we're evolved into, is long term partnerships between 2 people of opposite sexes in which offspring are raised. But you can't avoid the fact that for some people it just doesn't work like that. They are not sexually attracted to the opposite sex, and they are attracted to their own sex. They naturally form relationships with members of their own sex. It happens. None of us can control sexual attraction. Those who are normally sexed are attracted to some members of the opposite sex, and not others. And they cannot choose which they are attracted to and which not. There is enough evidence of women being serially attracted to violent men who are disastrous for them. It would be better if they were attracted to different men. But they're not. None of us can control who we're attracted to, whether we're straight or gay. And it's the same for gay and lesbian people who are, just the same as the rest of us, attracted to the people they are attracted to and not others.
Moving on from that, I used to be a Church of England priest. At the time when people came to get married we used to offer them a choice of the words of the service - basically one written in 1662 and a current (1970/80) one. The main difference I used to point out was in the preamble, when the priest tells the congregation what it's all about. In the 1662 service the first reason for marriage is for the avoidance of sin - that is, as a regulator for sex, a convenient safe place to keep it. In the modern service the main reason was that the couple should comfort and help each other. That's a big improvement! Ask anyone who has been married a long time what the most important feature is, and they'll tell you it's mutual comfort and support. People need it, it is a good thing. And gay people find that they need it just the same. Not all gay people, same as not all straight people do. But many do. Some years ago my doctor was gay. He and his partner had lived together for over 20 years at the time I knew them. So why should they be denied that? Of course, there is no reason. The argument is over whether or not the state should recognise them.
The same preamble that I mentioned earlier goes on to say that the couple belong to each other and begin a new life together in the community. This is very important. Marriage contributes to, but also depends on, its social setting. Any relationship needs support from outside, both formally and informally. It benefits the relationship and it benefits society. The same is true for lesbian and gay couples.
I used to know a gay couple, John & Peter, who were excellent people that had lived together for what amounted to all their adult lives. They were in their 60s or so. Suddenly John died. Now they had never put the property, their home, in joint names. It was in John's name, despite the fact that Peter contributed to the bills and mortgage. And when John died his family (brothers and sisters) legally inherited the house. They threw Peter out of what had been his home, onto the street, as they gave him what amounted to no notice. He had no recourse in law, and lost not only his partner and the love of his life but his home as well. That's simply, undeniably, wrong.
The way I see the present legislation about civil partnerships is that it goes some way to providing a homosexual couple with a framework for a long term supportive relationship in a social setting protected by a legal framework. I think all those are good things, good for the couple, good for society. If it isn't perfect, it's the best we can do.