How to tell you're in love?

I was diagnosed with BPD (Borderline Personality Disorder) since college, and I have abandonment issues. I don't believe in marriage but sometimes I believe my dream is to have a nice family, I love my fiancee but being attached to one man scares me. What if I'm a terrible wife, what if I don't love him. Things can go from hate to love to hate for me with him. Sex is more of a chore for me than joy but I was assaulted when I was young so that may be a factor. My wedding is around 6 months from now and to this day I still don't know if I love him or is he just the easy way, so I don't have to be alone.

How can you tell when you're in love?