I think maybe you're a little ticked off that Manager 3 has been able to repeatedly get the better of the other managers in your league.
Look, you're probably playing with a bunch of chuckleheads who don't do their homework, but what did you expect? Personally, I wouldn't play in an 8-team league unless it was a knockaround league where I knew everyone personally and there wasn't anything but trash talk at stake. I know not everyone thinks that way, but I think it's hard to find a league that shallow where everyone's playing smart.
What would I do? Take advantage. Sell high and buy low at every opportunity.