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Not an affair. He wasn't suicidal either. The husband however doesn't know about either. The uke used to hate seme - and the seme wasn't allowed to go into the kitchen or like certain areas of their house or be in close proximity to the uke. So he is sticking to those rules. I mean it's obvious from the wedding photo that uke didn't even like looking at the seme so it's just that.
Long story.
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Was forced to marry the seme because his parents had sponsored the uke's education. And his position in the company is only because he married the seme. Seme is too..weak to be incharge so the parents essentially put seme's "partner" in the leadership position.
The affair here is just the uke meeting with another chef for a job opening. But ends up declining it.

I'm only saying this as a possibility but....what if he was actually suicidal and his husband is just trying to keep him from remembering hurtful memories? Or maybe there was an affair?