I've come to the conclusion that the truth will set us free.
Is there a truth that you believe will set you free?
I can't get married because I lied to my fiancee about being in love with her.
If you are not in love with someone then break it off with them, but lying to them about your feelings and then agreeing to marry them is not right. Be honest and tell the truth to your fiancee.
I'm going to go to therapy about it. I've never been to a therapist, but it can't hurt.
You should be honest with your fiance as lying to her is wrong and deceitful and she deserves to be in a relationship with someone who loves her. If you think a therapist will help you through the process of being honest, then I support your decision to visit one.