At the end, you could see her tell.
Lisbon has this tell whenever she is lying, she will glance to the side and look back at whoever she was talking to.
When Pike asked her if she felt the same way he does, what did she do?
SHE GLANCED TO THE SIDE!!!
lisbon: jane ok, let’s go far away and be happy.
jane: that’s my girl
"He seems like a good guy."
"Good. Because you deserve to be with a good man."
Pike: Do you feel that way?
Lisbon: yes… I do.
If you came with me… to DC, you and me… together! What you think of that Teresa?
Lisbon, you lie so bad!
Look at her face! Like hesitant; she is carried away by the situation!
I’m going to need the assistance of the irreplaceable Special Agent Teresa Lisbon.
— Patrick Jane Irreplaceable (via redfree-eleven)