I slept with my brother-in-law when I cheated on my husband.
Why would you cheat with your brother-in-law?
I just thought it would be a funny thing to do.
Cheating in general is wrong and hurtful to your partner. Cheating with his own brother is even more cruel. You should reconsider your actions and apologize to your husband.
No way, I'm not going to do that. Plus it was only a one time thing.
It doesn't matter, you can't cheat. You are going to ruin the brothers' relationship, you should apologize.