i need information on getting out of a rental agreement lease! how can i get around this with out being sued?

when i moved in it was going 2 be 2 people but the situation has now changed.my name is the only name on the lease. i can no longer afford the rent on my own.:( I've located another cheaper place. please give me any suggestions that will help me take care of this problem with out harming my credit and leaving my land lord in a whole. thx