Lease renewal time...Unsure how to proceed

[Ashley Montgomery]

I have a property that has a joint lease. They have lived here for 2 years and it's time for lease renewal (in April). It is two roommates (guy and girl) that are no longer getting along. She wants him to move and I'm fine with her being the only one on the lease however, he wants to stay. Can I offer to only renew the lease for her? If so, what if he refuses to leave? Do I have to evict him?

They are the first tenants that I ever had and have always paid on time and taken very good care of the property. I hate to pick sides but she is a friend of a friend so she gets dibs on the lease. I am just kind of scared to inject myself in their mess. Any advice is greatly appreciated! Thanks!