It's a long and complicated story, so I'll just give the cliffs
-parents divorced a long time ago, but are amicable.
-dad lives far away
-dad flew into town for christmas, asked to stay with my mom for one night before he moved into a hotel
-mom has been seeing a guy for a long time. I'm currently living with him. when she told me my dad was staying with her last night, I told her bad idea, but if he does, don't tell her boyfriend. she didn't tell him.
- mom's boyfriend found out about dad sleeping over and is pissed and hurt that she didn't tell him.
I feel caught in the middle.