"relentlessly ridiculed" is correct and usable in written English.
You can use it to describe the situation of someone or something that has been subject to consistent, ongoing ridicule from others. For example, "John was relentlessly ridiculed by his peers for his quirky sense of style."
The child was relentlessly ridiculed by his peers, male and female alike.
He has already accomplished the impossible: He has made the first lady, relentlessly ridiculed by conservatives as a panting-for-power yuppie, look laid back.
Between repeated takes of one scene, the third rabbi relentlessly ridiculed Mr. Sendak, calling him Mr. Kiddie Book King and spritzing him in the face with water from a plastic bottle.
Proving both his media savvy and his masochism, Frey volunteered to intern at Gawker, the very site that ruthlessly and relentlessly ridiculed him in the aftermath of that little tiff Frey had with Oprah and the rest of the country a while back.
Perhaps she had learned the lesson of not taking sides from Mrs. Clinton, who was relentlessly ridiculed at the start of her Senate campaign for donning a Yankees cap and declaring she was a fan of the team -- even though she was from Chicago.
America Online aol, relentlessly ridiculed by the cyber savvy for its quirky desktop client, is slowly breaking free from its proprietary software solutions with the launch of AOL 5.0 later this year.
He stumped for government investment in aviation and ridiculed Prohibition relentlessly.
He ridiculed me relentlessly, in between shouting off-color comments at his comrades.
Reagan, heeding Churchill's vivid lesson of "peace through strength" (for which liberals ridiculed him relentlessly), prevented World War III "without firing a single shot," as Margaret Thatcher observed.
It is true that Thaddeus Stevens unleashed nasty, hateful invective on slaveholders, ridiculed incompetents, and relentlessly elbowed a cautious Lincoln toward emancipation.
But among the rank and file of security contractors, Blackwater guards are regularly ridiculed as cowboys who are relentlessly and pointlessly aggressive, carry excessive weaponry and do not appear to have top-of-the-line training.
