I'm Divorcing with You, Mr Billionaire!

I received a pornographic video.
"Do you like this?"
The man speaking in the video is my husband, Mark, whom I haven't seen for several months. He is naked, his shirt and pants scattered on the ground, thrusting forcefully on a woman whose face I can't see, her plump and round breasts bouncing vigorously. I can clearly hear the slapping sounds in the video, mixed with lustful moans and grunts.
"Yes, yes, fuck me hard, baby," the woman screams ecstatically in response.
"You naughty girl!" Mark stands up and flips her over, slapping her buttocks as he speaks. "Stick your ass up!"
The woman giggles, turns around, sways her buttocks, and kneels on the bed.
I feel like someone has poured a bucket of ice water on my head. It's bad enough that my husband is having an affair, but what's worse is that the other woman is my own sister, Bella.
“I want to get a divorce, Mark,” I repeated myself in case he didn't hear me the first time—even though I knew he'd heard me clearly.
He stared at me with a frown before answering coldly, "It's not up to you! I'm very busy, don't waste my time with such boring topics, or try to attract my attention!"
The last thing I was going to do was argue or bicker with him.
"I will have the lawyer send you the divorce agreement," was all I said, as calmly as I could muster.
He didn't even say another word after that and just went through the door he'd been standing in front of, slamming it harshly behind him. My eyes lingered on the knob of the door a bit absentmindedly before I pulled the wedding ring off my finger and placed it on the table.
I grabbed my suitcase, which I'd already had my things packed in and headed out of the house.