An Ethical Dilemma

What do you do when your pet Beta Fish is suicidal? Yup, you heard right, I think Rupert is trying to kill himself. I haven’t actually seen him attempt it, but occasionally I hear a large splash in his bowl and when I look over he’s bobbing around as if he has tried to jump out of the water. He currently isn't in any really danger; it would be a miracle if he could jump high enough to get out of the bowl. But the whole thing concerns me. It started the other day after I had cleaned and changed the water in his bowl. You’d think he’d be happier, but instead he’s doing this. To be honest, this isn't the first time he’s tried. Probably around six or seven months ago he was doing the exact same thing. I just don’t know what to do to help him. I’d get him a companion of some sort, but he’d probably kill it (it’s his fighting fish instincts and all). I just hope he gets better. I’d welcome any advice on the subject.