Do you think it's okay that I'm insanely in love with my therapist?
Why do you love your therapist?
I think I'm in love with my therapist because she's the only one who actually listens to me.
I'm glad you found someone who listens to you, but that is a therapist's job. They are paid to listen to you, and that is an unhealthy fixation you have by being in love with them. You need to find someone your own age or you can no longer visit this therapist.
I don't want to date anyone my age. I want to date my therapist.
You have no chance of a romantic relationship with your therapist. If you are expressing romantic attraction  to your therapist, it's likely that she will refuse to work with you.