The Lockhorns

An one-panel, gag-a-day Newspaper Comic created in 1968 by Bill Hoest, continued since his death in 1988 by Bunny Hoest and John Reiner.

The comic's protagonist are Leroy and Loretta Lockhorn, a married couple who hate each other.

That's pretty much all there is to it. The strips usually feature Leroy and Loretta making passive-aggressive, sarcastic one-liners at each other, whether to the other's face, or to some third party, though light satire of everyday life also abounds.

This comic features tropes such as:

 * Awful Wedded Life
 * Deadpan Snarker: Both protagonists.
 * The Eeyore: Both Leroy and Loretta, again.
 * Family Title
 * Lazy Husband
 * Lethal Chef
 * The Masochism Tango
 * No Accounting for Taste
 * Obnoxious In-Laws: Loretta's mother is a frequent target of Leroy's snark.
 * Perpetual Frowner: Everyone's range of expressions consists of "depressed and bored" and "infuriated", with only the occasional "grimly satisfied".
 * Punny Name: The Lockhorns are always "locking horns" with each other.
 * Women Drivers