Len, nothing the man has done takes away the children's right to a relationship with their father. The law has changed in the UK now so that whatever the 'wrong' parent had done, both are entitled to a comparable family home from the proceeds of the house sale, even if it means the resident parent radically having to downsize.
I agree with that. If the children want a relationship with their father, it must be allowed ... but they should remain in the custody of the mother, the injured party. If the law says otherwise it is an ass.
I don't think the law does or should define custody of the children as a kind of consolation prize for being the injured party in a divorce. The law decides on custody in the best interests of the children, not of the parents.
There are countless examples of situations where a woman has been the one who is unfaithful and, therefore, by your definition the man is the injured party, but the woman is granted custody of the children. I can think of three or four examples in my own sphere of friends or family.
Actually what this articles indicates to me is not bias due to sexuality but an assumption of bias in favour of one gender, i.e. a default that the mother always gets custody of the children.
So I wonder whether there would be the same publicity if it was the woman who broke up the marriage by having an affair (whether heterosexual or homosexual) yet was granted custody of the children. I doubt it.