The characters on the show are all contributing to how hilarious it is. There's Maryanne, the divorced alcoholic woman who won't give up on her ex-husband. She's a stalker. :D
Cybill has two daughters by two men, both of whom she divorced but they're all still in her life. The older daughter is also having some relationship problems, and the younger one is a typical teenage kid. The fathers/ex-husbands try to help out with every trouble they find themselves in but that doesn't always help. In fact, I'm not sure if it ever helped! But it's the thought that counts, and it's obvious they all love eachother.