Return the Deposit

[Joshua Rogers]

To keep this brief, I will simply highlight that a tenant agreed to another 6 month lease beginning in January 2015 (agreed via text...perhaps not the most legally binding, but nonetheless).  They decided to move this month after giving me 30 days notice, and I didn't mention the 6 month lease at that time (for fear they wouldn't pay their rent as a way of utilizing their deposit for rent).  So, they broke the lease 3 months early.  Rent is $1350 a month.  Disregarding damages and a few other issues at the property, does the single fact that they broke the lease entitle me to keep entire deposit? (essentially they owe 3 months rent, for a total of $4050.)  Thanks for the help.