I wouldn't lie. I'd say how hard it was to tell the truth and then tell the truth.

Do you feel you have to do certain things, be a certain way, for your therapist to care for you? Is that a feeling you have had about other people in your life? That is worth exploring in therapy. Is your fear of "disappointing" people and losing their love making you unable to have a real, open, honest relationship with them?

The other thing is, there are probably reasons you didn't have the discussion with your coworker you had planned. Did you really want to? Or were you agreeing to just so you wouldn't "disappoint" your therapist? Or, is it that you did want to and just couldn't for some reason that you have not yet overcome?

All of this is such important stuff to talk about. If you lie, you'll talk about none of it. And you will prevent real engagement and intimacy by hiding the truth and having a relationship not based on who you are but based on a "false self" you are creating for someone else. Maintaining the false self is no fun and doesn't get you close to people.