The 26-year-old actress wrote a "clap back" in a series of tweets after fans criticized her bedroom selfie with the 33-year-old former "The Bachelorette" bachelor.
Hyland had shared a picture Monday of herself and Adams snuggling with her dog in bed.
She took to Twitter after an Instagram user admonished her for not keeping her "sexual life" and "the details [of] her personal life" private.
"So I just have to say I'm so sorry...FOR POSTING AN ADORABLE PICTURE BECASE CARL WAS ACTING LIKE THE NUGGETIEST SNUGGLW BUG!" Hyland wrote.
"Couldn't let that moment pass without getting a picture."
"I do want my privacy. Especially in my relationships. I've made the mistake in the past on being way too open and talking way too much about them. This time is different. It's special. And I will share what I seem 'appropriate' on social media because I still want you all to be updated," she explained.
"Because you're the greatest fans in the world."
The "Modern Family" star followed up by addressing speculation she was naked in the photo.
She told fans to not be "hypocrites" by liking other posts with nudity, advising to "either be conservative on all fronts or free the nipple."
"I just realized I'm being criticized for being naked... which you don't even know if I am!" the star wrote.
"You can barely see any skin but it's ok for Instagram models to roll around in the sand ACTUALLY naked? (I mean I'd post that too if I looked like that)."
Hyland and Adams were first linked in October after celebrating Halloween together.
The actress' "Modern Family" co-star Julie Bowen said Saturday to Entertainment Tonight that Hyland is as "happy as can be" with Adams.
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