The singer has appeared on the show for two days in the row, first helping his mother get the substance abuse treatment she needs, while also talking about his struggles with addiction and mental health.
In a video package where he claimed he has been diagnosed with multiple personality disorder, schizophrenia, acute anxiety and depression, Carter also called out his brother for allegedly not reaching out to help him when he went to rehab in 2017.
"After going to rehab, Nick didn't come, my mom didn't come, nobody came," he claimed. "I get a tweet, a public tweet from my brother saying if you need any help with rehab, I'm here. You live in Las Vegas, 3 hours away, hop your ass in the f--king car and get here!"
"Come see your brother, your little brother that you care about," he said, putting air quotes around that last part. "You need to make amends to me, you need to apologize to me. I haven't even met my nephew. I'm sure people will be looking at this like, 'Oh my god, he's manic, he's this, he's that.' I don't care. I don't f--king care.'"
He continued to rail against his brother on social media after the episode aired in some markets.
"I've been sober for 2 years growing every single day, getting stronger, yet, all people seem to care about is that my brother wants nothing to do with his family," he tweeted. "He's playing victim to circumstances that he created. You cant create your own storm then get upset when it rains."
After some of Nick's fans criticized Aaron for airing family drama, Aaron reminded them that his brother did the same in his 2013 book, "Facing the Music And Living To Talk About It." He tweeted, "I'm still upset and find it to all be very contradicting that you 'fans' are totally cool when he releases a book about his whole families shortcomings. What's wrong with you people?"
"Nick started it by using his families shortcomings for profit when he wrote a book," Aaron said in another tweet. "Also he didn't even show up at our sisters FUNERAL because he had a concert at a bar two hours away and said he didn't want to be apart of family drama when we were burying our sister Leslie."
Other responses to his critics included, "All you fake ass f--king fans. Unfollow me NOW!! Disgusting," "I didn't start this feeding my brother did. Do your research. And now it's my turn to speak," "Gotta love cyber bullying backstreet boy fans.@backstreetboys" and "We haven't been brothers since our careers started. We've been aquatinted."
He went on to accuse Nick of refusing to help their late sister, Leslie, who died of a drug overdose, as well as their mother.
"NOW the @backstreetboysfans are #CyberBullying they are notorious for it," he continued. "Absolutely appalling after what I just did for my mother. And once again. He wasn't there I was the only family member to be apart of my mothers intervention."
He also said the "majority" of BSB fans were bullies, he'd "never forgive them after this" and thanked his own fans for not being anything like them. "I'm still learning just remember these people need help too. So if you backstreet boy fans need anything I'm always here," he added, along with the hashtags #CyberBullying #IForgiveYou.
That sentiment echoed what he said on "The Doctors" today, when asked why he often responds to his haters online.
"I'm guilty of it, so I know if someone comes and bullies me, they're hurting inside and I want to talk to them and I want to help them," he explained. "I feel like I have the ability to reach the masses. All of you would probably say ignore it, I'm not going to ignore them because they're hurting."
"I'm constantly accused of being a crackhead and a meth head and I have AIDS. What I'm doing, I'm making everybody play my game. I'm not playing your game. And my game is there's a much deeper introspective outlook I have in regards to a bully and it's that they're hurting inside," he continued. "No one would ever say these things to my face. I want to put them on live and say hey, what did I do to you. Are you okay? How can I help you? If there's something I can do, I wanna do it and I want the rest of the world to follow suit. Stop ignoring a hater and bully, you're making the world worse in my opinion."
The results of Carter's drug test were also shown on air during Friday's hour. According to Dr. Travis Stork, Carter tested positive for marijuana, opiates and benzodiazepines. While he admitted to loving pot and his medications explained the benzos, Carter denied taking opiates in the past two years. Eventually -- saying he forgot -- Carter said he recently took hydrocodone after getting six crowns on his teeth. He swore he wasn't mixing and went off his other medications at the time.
When Dr. Judy Ho told Carter it could be problematic for him to be smoking marijuana while on his other medications, he announced he was "quitting" -- only to tweet out later today that he would continue using it until undergoing a comprehensive mental health evaluation with Ho, which he agreed to on the show.
Carter also opened up a bit more about his addiction to huffing, which he first revealed on Thursday.
"It started when I was about 16. My sister Leslie, who passed away from an overdose, got me into it," he explained. "I didn't really touch it until I was about 23, right after I did 'Dancing With The Stars,' and then I started going to Staples and Office Depot and different places and buying it with cash so it wouldn't be reported on receipts so no one could trace me."
"I was huffing because I was really f--king stupid, sad," he continued. "I was huffing because I'm a drug addict. I'm a drug addict in recovery. You might not look at me smoking weed as recovery, but I do."
He said he hasn't done it again since relapsing immediately following his 2017 rehab stint. He said he drove back to rehab right after his relapse.
Near the end of the show, Carter pointed out how a lot of the attention surrounding him has been negative, even though he swears he's in a better place.
"What I'm doing is an act. I'm showing the world that people pickup only on drama. Where do you show anything about my accolades here? You don't," he said. "The world doesn't. What they're showing is the negativity only. They're not showing the accolades. The bullying started to get worse the last two years, since I've been clean, sober and I've started making millions of dollars again."
To highlight some of the more positive aspects of his life, he tweeted on Friday about helping a woman organizing a toy drive for a children's cancer ward reach her goal of 1,000 toys by donating 400 himself. He added that he'll be driving the toys to Vancouver himself following his concert tonight in Washington state.