how do you move on from someone?

I've been in love with this person for the past 7 years. We are on very good terms, best friends basically, She knows that I am in love with her, and she was also once, but we never dated nor were in a relationship. Very complicated. We value each other as friends. But lately i feel that she doesn't feel at all for me. How do i move on from this without cutting her off completely? Therapy is expensive, i cannot afford it. It would break me into a trillion pieces if i see her with someone else?