Therapists know that clients don't want to tell all and that they sometimes "lie". It is understandable and okay. This stuff is hard. So she won't get mad and she won't hate you. You don't have to tell all right away. Just start somewhere and work from there.

When I have been afraid the anticipation was always worse than the actual thing that I was afraid of. I have always pushed myself to just do it and I have never been dissapointed. Actually, facing what you are afraid of is actually a relief because the anticipation is much worse than it actually is.

Why should you do this? Because this is how you get better.