Jonny Mitchell appeared in the 2017 series of Love Island alongside Mike Thalassitis, who was found dead in a north London park on Saturday.
He tells Sky News Mike was "one of the strongest people I knew" and strongly criticises the level of care offered to those in the villa.
I was never really sure about going on the show. I'd never watched it. I was unsure about whether I was ready.
After one day I decided it wasn't for me, all the cameras were too much and I made it clear I wanted to leave, but it was extremely difficult to get out.
The producers told me: "But Jonny, you're going to be famous," and said leaving wasn't as simple as that. They used mental tactics to get me to stay. They were very persuasive.
The psychiatric help on the show is more to tick a box than real help. The psychiatrist is there to look after all of the team and the contestants, so it's not as if you can just get help straight away.
I did see the psychiatrist when I left, but it was a formality, a 5-10 minute interview where I was asked: "Are you OK? Are you ready to leave?"
It was no preparation for returning to the real world. You have no phone or contact with the world outside when you're on the show. It's like being in a bubble.
You have no idea how you've been portrayed. It was a real shock when I got my phone back and found out what people were saying about me.
I received all sorts of abuse and even death threats.
My only contact with them [the show's producers] was when they called me the day after Mike died. I think they were just covering their backs.
Mike was one of the strongest people I knew. It's very sad what happened to him.
They [the producers] look after their winners, their number ones. Ninety percent of people on these shows don't do anything afterwards. I'm lucky as I have worked in my family's business, so I had something to fall back on. I just did it for a laugh, I wasn't looking for a TV career.
Lots of the contestants that did well in these shows put on an act, appeared to be a bit dumb to be more likeable.
We do a lot of business in China and when I look at their youth, I think they would laugh at what our next generation aspires to be, what their life expectations are. They would laugh.
I'm campaigning with a lot of others to change the before, during and after for people on these shows.
Sky News contacted Love Island's production company, ITV Studios, which said it is "absolutely devastated to hear the news about Mike" and insisted contestants are able to access psychological support before, during and after appearing on the show.
In a statement, ITV Studios said: "Care for our islanders is a process the show takes very seriously and is a continuous process for all those taking part in the show.
"We ensure that all of our contributors are able to access psychological support before, during and after appearing on the show. The programme will always provide ongoing support when needed and where appropriate.
"We also discuss at length with all of our islanders, before and after the show, how their lives might change and they have access to support and advice to help with this."
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