Grizabella
She can be well bossy; the kind of woman who makes her children be what SHE wants them to be rather than themselves (wait - she is my mother... )
I'm in agreement with gregory about this card representing the negative side of the Queen of Pentacles---someone who will try to make someone else over into what she wants them to be. This would be one of the traits of a reversed Queen of Pentacles. He may have had a mother like this or a relationship like this and it left him gun shy. Maybe he's seeing hints of this trait in this woman and that would contribute to it becoming a fear of his.
I hope this makes it a little more clear what I mean.