There is no pride in telling people bad things under the guise of “truth”. Try to say nice, inspiring things. It’s really hard to both accept a person as (s)he is and give him/her motivation incentives. They can fall into a depression about their imperfections without you.
It is a subtle point, whether one is responsible for ensuring a partner’s happiness in a relationship. I think, (s)he is not responsible. Who can force one to be happy? But we are responsible for giving everything necessary for his/her happiness. Drive up, open the door, beam, and let him/her decide if (s)he really wants to sit or maybe walk.