It can be quite sad at times. I had a pair of red neon swordies that had pretty much paired off a while back. Huey would never let Blondie out of his sight, sadly Blondie died while having babies and Huey was devastated. He wouldn't eat or anything, just hung out in the corner where I found Blondie's body and died a few days later. Meri hung out with him the whole time and wouldn't let anyone near him, she'd go over and gently bump him occasionally like she was trying to get him up and moving around but he'd just ignore her. I swear she even tried to get him to eat - I tried dropping shrimp pellets down to him (his favorite food) and Meri would swim over to the pellets and then turn around and look at him as if to say "c'mon Huey there's shrimp pellets over here, just for you!".