Can 1 person break a joint lease with the permission of the landlord but not the other people on the lease?

Question Details:

My ex-girlfriend and I signed a 1 year lease in 08/10. We had a friend move in who was also added to the lease. I would like to move out and the landlord has agreed to take me off the lease but my roommates think that I should still be responsible for my share of rent. So can I move out and break my part of the lease with the landlord's permission? Important Notice