Mercury represents our communication style and intellectual processes. Strong aspects between your Mercury and your partner's planets and/or points favor communication and sharing ideas.
Mercury Inconjunct Pluto
You have a concept or decision created during the tumultuous events of a previous relationship that is bothering you now if only unconsciously, sitting between yourself and your romantic partner which limits your ability to love or experience true partnership. Your conversations will bring it up and eventually cause you to acknowledge and confront events from your past in order for you to reach understanding and be free to think about it in another way. When the Mercury person is inconjunct the Pluto person, your partner carries such a burden and your only way past it is to help release the emotion behind their thoughts.