I agree both mother and father should be accountable for their offspring's welfare.
And I think that marriage is best apprehended as not merely a contractual obligation, but a sacrament. But there are legitimate reasons for government to support and accord special status/recognition to it.
It used to be that tolerance in the country meant toleration of things that would never be held as equivalent, equal or prefered practices. Tolerated meant "not criminalized."
Now we're expected to obliterate instititutions and social mores that have proven themselves over the course of long history--and for what?
Nothing as good. That's certain.
[...there are legitimate reasons for government to support and accord special status/recognition to it [marriage].]
I strongly agree with you on that statement, but if you were pressed to support your opinion for the record, could you list them and even briefly summarize those reasons?