Love conquers all.
No matter how badly Al Bundy and his family talk about each other or treat each other, they still love one another, and prove it. For Example, Al always complains about having sex with Peg, telling her that he loves her (let alone likes her), or even go anywhere in public with Peg. In the episode where Al was the guest speaker at a homecoming dance, he nearly punched a man when the man started coming on a little too strong to Peg.
In that same episode, Bud made his usual jokes about Kelly being a virtue-less woman of cursory intellect while Kelly chided him for being friendless and devoid of mating skills. However, when a young lady made a mockery of Bud by hanging his pants from the ceiling and letting the whole party see Bud jump for his clothes in his underwear, Kelly came to his rescue. Kelly got even for Bud and tied a sign on the girl forewarning all not to “mess with a Bundy.”
The characters on Married with Children do and say everything you want to towards your loved ones, but should not. And no matter how awful their insults and deeds may be, when it truly matters, they really do prove that they love one another. Insults and rudeness may be the fabric of the humor in Married with Children, but it is the love that the characters embody for one another which is the thematic truth and the golden thread which has weaved the show seasons of success.