someones stealing electricity and my landlord knows about it?

ok so after reviewing my electricity bills after moving into my apartment ive noticed some serious issues, mainly them being too high (compared to the rest of the building) now my landlord finally openly admitted that someone is also on my meter, and pretty much stated to deal with it, he will reimburse me, Im not ok with this and i already called my electric company, they said theres nothing they can do about it, to call the code enforcement office in your town, well i did that and he said theres nothing he can do about it either, im at a loss here and im not paying to heat someone elses apartment, i really dont have any options right now about moving to a new place since im broke as it is, what can i do about this to get the money im owed, since i was never reimbursed for the months he was using my power, and how can i go about legally getting the landlord to correct this issue since the guy using my power is pretty much living here illegally