I don't know. I have been feeling pretty crap about ending up a single parent a second time, with all my money going on legal fees and it being very hard to get my confidence back to believe that yes, I can do this. I believed it no problem first time round, but second time, maybe as a result of several years of belittling and other forms of psychological abuse, I have felt on the floor.
To read that my children can be as happy as the other children in the world, to read the positive stories here, yes, that has helped. I agree re the thread title, but also with the comment that objective good is needed to balance objective bad.
If all else is equal, two committed parents in a loving relationship are better, I am struggling to find an argument against that (except that I have no experience of this, so I am talking about ideals). But people become single parents because all else is NOT equal and that is the only way they can see of making it better; or because they are deserted and have no choice. The message that your children can and will survive, even be as happy as others, is important.
I am not saying it is a positive lifestyle choice; but I actually think, now, yes, it is the way it is and I need to make it work. I would not have chosen this position pre-children; but knowing what I know now, I would not change it.
So, yes support for all parents, but also better relationships education; better understanding of how the pernicious effects of childhood abuse affect adult relationships; but mostly, better appreciation that families have always come in all shapes and sizes and none should be discriminated against.