Carla and Shalisa signed a lease to rent a condo for one year for $1,500 rent per month. Carla and Shalisa were both working and agreed to split the rent. After 3 months, Carla lost her job, packed up her belongings and went to live with her parents in Europe. Shalisa has not paid the current month's rent and offers to give the landlord half. She told the landlord to get the other half from Carla. The landlord is demanding the full $1,500 in rent from Shalisa and took her to court for 'breach of contract'.

How should this case be decided and explain why?