Was it a merman who broke your heart? Did a merwoman steal him away? Is it revenge that you want? Maybe just a tiny spell to make him yours...forever ?
Or did your lady-love swim to bluer waters? She abandoned you just as the surf got a little rough, before the tide washed out? No problem! I can make her desire only you! Now, don't cry, Honey. You'll smudge your seaweed. Come... have a nice hot cup of blowfish bouillon.