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'Project Runway' Star Chrissy Teigen's Bullied Me So Much ... I Have Suicidal Thoughts

Michael Costello says he nearly took his own life because he could no longer deal with the trauma -- personally and professionally -- which he claims Chrissy Teigen brought down on him.

The "Project Runway" star's accusing Chrissy of a yearslong campaign to get him blacklisted from the industry, because he says she mistakenly thought he posted something racist all the way back in 2014.

Costello claims no matter what he did to try to convince Chrissy the racism allegations were untrue -- he says Instagram proved it was a Photoshopped comment he didn't write -- she persisted, and told him his career was over.

He also posted screenshots of the alleged messages from Teigen, in which she says, "racist people like you deserve to suffer and die" ... and issues the veiled threat about his career.

Michael claims Chrissy, along with stylist Monica Rose, followed through with this by using their power to get brands and companies to not work with him.

The designer says he's suffered tremendously, and is opening up about it now in an attempt to set himself free from depression and suicidal thoughts.

Costello claims it's gotten so bad recently, he told loved ones he thought taking his own life was the best way out.

Of course, Michael's allegations coincide with Chrissy issuing a lengthy apology for her past behavior online ... which she called trolling, and attributed to her own insecurities and immaturity.

If true, it seems the Michael situation is a different beast with different context ... but it's certainly not any more tolerable.

We reached out to a rep for Chrissy ... so far, no word back.

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