Is your character alone in the world? Have they lost a family member? Do you want to show that no matter how much time has passed, they just can't get over it? It's easy: just have them watch a home movie of the happier times with that family member. Said movie will often include one or both parties declaring outright how much they love the other, just to drive the point home. For bonus unhealthiness points, have the grieving character rewind the tape and watch it over... and over... and over... See also Alas, Poor Villain, Really Dead Montage and Happy Flashback.