Forget the fact you BOTH moved way to fast, and got in way over your heads, with the year lease. Neither of you knows the other well enough, and neither of you is honest with yourselves or your partner, enough to even call this a relationship, its not. This is a very bad soap opera, and you two don't even work together well enough, to maintain an apartment, or a relationship. Either pay with cash to separate, or pay the emotional price of being with someone you don't love or trust. Sorry for your loss, you both share the blame though, and a very expensive lesson in life.