MARK Salling's friends have opened up about the disgraced star's troubled final days, revealing that he was living a secluded life.

The former Glee actor, 35, was found dead on Tuesday after an apparent suicide, just weeks before he was due for sentencing for possession of child pornography. In December, he pleaded guilty after having more than 25,000 explicit photos and videos of children discovered on his laptop and hard drives and was facing up to seven years in jail.

Salling's death has proven divisive, with many - understandably - believing he shouldn't be remembered fondly, and criticising his former Glee colleagues for their tributes to him.

In the years before his death, the disgraced star had been living a reclusive life, the spotlight having shifted away from him after the series wrapped in 2015.

According to two friends who spoke to People magazine, Salling was only really speaking with family during his final months.

"He was close with his family, but as far as friends go - he maybe had those acquaintances he communicated with every once in a while, but he pretty much isolated himself," said one source

"He didn't really have a relationship with too many people."

One source went on to describe what he was like before his downfall.

"The Mark I knew was charismatic, he was funny, he was musically talented - he was a really cool person," the friend said.

"This other dark side of him was completely shocking to everyone close to him ... Close people who didn't talk to him are still sad about it.

"They loved him because of the person he was before all of this happened. There's a level of sadness with everyone, but the sadness is from afar."

Meanwhile, another friend admitted that Salling had been tortured by his waning career, even before his arrest.

"His career was off the boil, though; he was kind of the quarterback that peaked in high school, still dining out on Glee. Eventually, though, he started to focus on his music, which seemed like a good thing. That's where he should have been focused to start with," the source told People.

"But then the child porn thing came out, and people were so shocked. … It quickly started to become clear it was real, and then the few people still around him iced him out."

According to the Daily Mail, sources claim Salling felt he had "nothing to come back to" after prison.

His worried family called 911 on Tuesday at 3am, after realising he was missing. In the frantic call, they told the operator that he was "depressed and suicidal" and hadn't been seen since the night before. His body was discovered hours later at the Los Angeles River in Sunland, near where he lived.

If you are experiencing mental health issues or suicidal feelings contact Lifeline in 13 11 14 or BeyondBlue 1300 224 636. If it is an emergency please call 000.