The "Paparazzi" singer and the celebrity blogger used to be so close that they went on vacation together, but they had a big public falling out recently.
Gaga says that the breakup stems from a period where she was in the hospital recovering from a broken hip and Perez posted a snarky picture of her in a wheelchair on his blog. She urged her fans to boycott Perez's blog and accused him of bullying.
Later, the fight escalated when Perez was spotted looking at an apartment for sale in Gaga's NYC building and she accused him of being a stalker. Perez responded that he didn't know where she lived and that he looked at a dozen other apartments the same day.
Now, the blogger and the singer are using Twitter to snipe back and forth at each other. Perez fired shots by posting multiple nude and semi-nude pics of the "Applause" singer, some of which yu can see here (link NSFW).
Since then, he switched his allegiance to Gaga's rival Katy Perry, tweeting about how great her new single is. Katy recently passed Gaga as the most-followed female celeb on Twitter, and Katy's album "Prism" is currently outselling Gaga's latest release. Ouch!