Assertiveness is no more your 'trait' than it is 'instilled' in you.As far as being assertive that trait is instilled in black because they must assume the role of male and fenale. Not all black men are like that but most sorry brothers get it together. I love not assuming the role of a man but in a relationship you use the talent in the room if a mate has one talent that you are lacking then you must compensate as follows to succeed.
It is a behavior that you were drawn to, liked, and embraced.
You probably aren't the most qualified to freely distribute 'relationship' advice!