What I want to talk about more is the (b). Who will like an over-smart person? Nobody will. Why? We feel threatened by those over-smart people. Accordingly not a single man wants to be threatened by his girlfriend or wife ever. Then how should a girl make an attraction with intelligence? My suggestion is to use the intelligence on everything but your boyfriend.
If you are an accountant, don't use your counting ability on your boyfriend's account. Similarly, if you are a psychologist, don't 'use' your psychological knowledge analyzing your boyfriend's mind – he is not your rat, or guinea pig as someone called.
I suppose that people feel naturally insecure while interacting with a person with psychology background no matter how the person acts. Or maybe those psychologists are by no means conscious of how they hold a set of invisible questionnaires to test people every day. Probably the two views are both true.
How many different kinds of relationship do we have with others? We need to learn more how to deal with it. We need to fulfill the different roles.