I remember reading a short story in an international magazine. Here are details I recalled:
Time Tourism was a norm in the story.
A couple wanted to see their own marriage ceremony. So, they toured back in time with a "Time Guide".
They were sitting in the back bench of the church when the lady pulled out a pistol from her purse and the Time Guide jumped. They had bribed the corrupted system to sneak a weapon back in time which was prohibited by the law.
They wanted to get divorced possibly because the man had cheated. And, they didn't want to go through all the pains of the divorce. So, they decided to stop their marriage from happening by threatening the marriage ceremony by pistol.
In this adventure, they got separated from the Time Guide. And, they couldn't get back to present. The controls were on their wrist device.
They even visited their childhood selves and when the charges of their wrist devices went low, they frowned at the tourism admins who could monitor everyone. Then, they decided to kill the mankind by giving the first humans future infections.
They thought they were going to die million years before their own time (their wrist devices were fully discharged and they had no food and they were cold), when they spotted tourists hidden in a cave. Nobody had helped them. They were actually there to see the birth of mankind. This couple was actually destined to start the human race and that's why admins didn't let them return to present.
In the end, the couple tricked the tourists and the tourists ended up starting the human race.
And, our heroes also fell in love again.
Can you please identify this short story?