Just a hypothesis,
I think they were lovers in their high school days and since a lot of people is not yet open to any other sexualities, that led me to think that the top's father is homophobic.
Remember the time where the Top shows some glimps of his memories of bottom with the top's father and him being anxious and being confronted by his father. I think the bottom did something, like revealing that they were in a relationship and the father went furious about it questioning the Top if its true and shit happened which led them to be separated.
That's the reason why the top married a woman following his father's demand or something and also the reason why he is afraid to tell his father about their divorce with his ex wife.
I just based it on some hints in the series but feel free to correct me if I forgot some details.
I understand nothing, but I pity the ex wife.
If her ex husband is just as bad as what she said, no wonder she had enough with whatever he did.
Also, it's so unclear of what happened in the past.
What made the top to run away from bottom?
Where did the bottom go and chose to appear now?
What happened to the top to make him acting so weird and sensitive whenever someone brought up his father in the conversation?
The genre is horror and tbh I do think bottom doesn't act like a normal human. He's too creepy. Just what is this story about.......... the artist should have given the readers some past scenes so we can understand a little about the whole situation....