Mirror Crossed by L. J. Maines

Scarlet wiles away hours writing physics equations on the secrets of mind reading; subconsciously hoping this would bring her closer to finding love. The underachieving anarchic genius is piecing together the puzzle that she has been reading the mind of her soulmate from the age of five.
The closer she comes to finding out the truth about him, the more people begin to question her sanity. The soulmates will take vastly different paths in life into adulthood, and end up having contrasting lifestyles. Faced with potentially being institutionalised, Scarlet has to battle to prove she is right in order to find him.