Provide proof that we live in a moral universe.
Wrong question.
Evidence that we live in a moral universe: We care about morality.
How many times have you appealed to morality "defined by us" as a standard of behavior?
The absurdity is that "defined by us" morality is no morality at all.
Also, how is doing bad things to people who do bad things moral?
You don't believe in self-defense, then. If a young girl is being attacked by a robber, a rapist, a murderer ... you would call her immoral for defending herself with a weapon and doing bad things to her attacker. She must submit to the robbery, the rape, to die ... or be called immoral by you.
Funny how you do nothing about the immoral robber, rapist, murderer. You help the immoral instead of the victim ... and you call this "morality"?
If there were a universal standard, we certainly haven't found it.
You confuse rebellion against a universal standard with an inability to find the universal standard.
Same-sex marriage and child adoption are not longer "bad things" - to the contrary, children raised by same-sex couples are exposed to far less domestic violence.
Liar.
Divorce is not longer a "bad thing."
Liar yet again.
" Divorce represents one of the most stressful life events for both children and their parents."
That's the thing about "universal standards" - there are so many different ones.
Yes, there are an infinite number of wrong answers.
1+1 = 3 is wrong. 1+1 = 4 is wrong. 1+1 = 5 is wrong ....
That does not mean there is no right answer. That does not mean that it is impossible to find the right answer. People who argue what you just argued are beyond stupid, you are foolish.
The stupid can't help it; the foolish choose it. The upside is that you can choose to stop being foolish. Repent.