Best Friend Status Sucks?

This is more of a wanted opinion from multiple people to help draw some sort of a conclusion on the subject. A simple “social experiment” if you will.
Here’s the background,

I’ve always wondered why a relationship needs to have any type of physical attribute. Sure I’m human, and physical affection is probably going to happen, but I think ideally it doesn’t have to. The physical part of a relationship should compliment the existent relationship, not define it. That being said, the following was brought to my attention, which influenced my initial theory

A girl that I would consider a respected friend said to me, “I know why you don’t have a girlfriend”. Now coming from my past experiences with the opposite sex, I know why too, but there is no way she could have known “that” reason. She further elaborated on her statement and told me that I’m “good friends” with all the girls I know, because I show the same affection to them. I agreed, seeing I do come off as somewhat forward, but that’s who I am. She told me that it was the lack of showing sincere interest in the opposite sex more than a mere friendship was the reason to my lack of relationship.

I agree with her statement to an extent. If the concept of “you marry your best friend” is a valid statement, is there a line between “friendship” and “relationship”? Or are people with my same view just insecure?