That's a good question - the landlord could potentially add additional fees on top of the unpaid rent, but as far as interest goes, I'm not sure. But if OP can't afford the rent and can't find a subletter, IMO it's best to cut losses, find affordable place to live before his credit score is affected, and go from there.

OP, as long as your wife's name is on the lease, she doesn't just get to leave you high and dry with the rent.