Tenants broke up. She wants to sublease?

[Enrique Batallas]

Hello all. New landlord here. 

   I rent out a 2/1 house near a university. The tenants in question are amazing. However, They have broken up and I got this text today  

     "Tom and I have ended our relationship however I would like to stay in the house. What are the possibilities of subletting the spare room if I can find someone to move in?"

More info: They signed a year lease until June 2015. They also signed the lease together, both names. They also paid a months rent in Security deposit and a 400$ pet security deposit. 

     How can i go about this? End the lease all-together? No fee, re-do a new lease with the new person? 

Should I say "too bad" and continue collecting rent? My lease states that it is 2 months Rent to break the lease. I rent the house for 1650$ including Utilities.

A fellow landlord told me to do the following: Keep both tenants name on the lease. Allow the girl to sublease, where she drafts a sub-lease agreement complete with a "subject-to master lease" on a month to month. This way if anything goes wrong I can go after the girl AND the ex bf. In this scenario however I fear that if the new subtenant does any crazy damage, the main tenant can prove I knew she was subleasing and that she is not on the hook for that.

BONUS INFO: My tenants  do not have jobs, their parents pay for their rent. late 20's on scholarship responsible.

     I want to make sure I take all the correct steps to protect all parties involved, especially myself. Thanks all.