Roommates, Rent and Brokers Fees

I think Broker's fee just gets eaten. You got the place, you lived a year, the purpose of the broker has been met and used up. Half the security deposit gets returned to the person leaving though. The staying person will charge that to her/his next roommate.

Unless it's a really good place and there is dispute as to who leaves. Then the person leaving gets some money to leave. If half the broker's fee is that amount, fine.

ETA: I don't think the leaving person should get half broker's fee back. Maybe a quarter of the total? Yes, the person staying won't have to pay for another broker fee, but neither is that person going to ever be recouping that cost. Are you prepared to lose this friend? Why didn't you have an Oh Shit plan in place?

If you both left at the end of the lease, neither of you would get the broker's fee back. I agree with Tate that you might come to a settlement with the stayer paying something to the leaver. Both of you might want to take a long hard look at the circumstances that make it difficult for you to live together, because these are likely to resurface whenever you live with someone else. Before you embark on another roommate venture, you might want to write down some of the things you would absolutely have to have in a roommate agreement. You also should let go of some things. If you end up with something that looks like Sheldon's and Leonard's roommate agreement on Big Bang Theory, maybe you should reconcile yourself to living alone.