Am I right in thinking that every relationship tends to balance out stereotypically masculine and feminine personality traits?

Certainly true in my relationship, ishly. The irony is she was raised hyper masculine, and she is not particularly feminine, but still craves a masculine partner. Too much masculinity, tbh. Less craziness, but also less bonding and closeness.

She could be a lot more feminine, but she's too tough and stubborn to show any vulnerability. Only when she's tired, lul. Basically a different person when she's about to fall asleep: then the soft part gets shown. No pun intended. The balance is off.

Masculine and feminine qualities are always a part of any relationship and any individual. The difference is the ratio, in my opinion. I think those qualities can definitely be skewed too far in one direction or another.